Michael Carlson PhD
Professor of Research
Room: CHP 133
Phone: (323) 442-0868
Michael Carlson is a social psychologist and occupational scientist with expertise in research design and statistical analysis. He completed his undergraduate work at the University of California, Irvine as a triple major in Anthropology, Social Ecology and Psychology. At USC, he earned master's degrees in Psychology and Applied Biometry (Biostatistics), and his PhD degree in Social Psychology. Within the USC Chan Division of Occupational Science and Occupational Therapy, he participates in the generation and ongoing oversight of research grants, such as the Well Elderly Project and the Pressure Ulcer Prevention in Spinal Cord Injury project. In addition, he teaches quantitative skills in the graduate program. To date, he has authored and co-authored more than 40 peer-reviewed articles on occupational science, occupational therapy, psychology and medical science. HIs articles have appeared in the American Journal of Occupational Therapy, Journal of Occupational Science, Journal of Personality and Social Psychology, Psychological Bulletin, Journal of Gerontology: Psychological Sciences, and the Journal of Pediatrics, among others.
Doctor of Philosophy (PhD) in Social Psychology
University of Southern California
Master of Science (MS) in Applied Biometry
University of Southern California
Master of Arts (MA) in Psychology
University of Southern California
Bachelor of Arts (BA) in Anthropology
University of California, Irvine
Bachelor of Arts (BA) in Psychology
University of California, Irvine
Bachelor of Arts (BA) in Social Ecology
University of California, Irvine
Clark, F. A., Jackson, J. M., & Carlson, M. E. (2004). Occupational science, occupational therapy and evidence-based practice: What the Well Elderly Study has taught us. In M. Molineux (Ed.), Occupation for occupational therapists. (pp. 200-218). Oxford, UK: Blackwell Publishing. Link to full text
Carlson, M. E. (1996). The self-perpetuation of occupations. In F. Clark & R. Zemke (Eds.), Occupational Science: The evolving discipline. Philadelphia, PA: F.A. Davis.
Juang, C., Knight, B. G., Carlson, M., Schepens Niemiec, S. L., Vigen, C., & Clark, F. (2017). Understanding the mechanisms of change in a lifestyle intervention for older adults. The Gerontologist, Advance online publication. Link to full text Abstract →
PURPOSE OF THE STUDY: This study investigated the mechanisms of change underlying an activity-based lifestyle intervention, an occupational therapy program aimed at promoting healthy habits, and routines in older adults. We examined two activity-relevant factors as potential mediators linking the intervention to reduced symptoms of depression: activity frequency and global perceptions of activity significance. Social connections and perceived control were assessed to understand how activity-related factors relate to reduced symptoms of depression.
DESIGN AND METHODS: The sample consisted of 460 multiethnic community-dwelling older adults aged 60-95 years. Participants were randomly assigned to a 6-month lifestyle redesign intervention (n = 232) or a no-treatment control (n = 228) condition. After the 6-month period, 360 individuals completed post-testing. Latent change score models were used to represent changes from baseline over the experimental interval. Structural equation models were applied to examine the indirect effects of the intervention on reduced depressive symptoms.
RESULTS: The results demonstrated significant indirect effects from intervention receipt to decreased depressive symptoms via increased activity frequency and activity significance. Higher activity frequency was linked to fewer depressive symptoms via heightened social connections, whereas increased activity significance was associated with fewer depressive symptoms via enhanced perceived control.
IMPLICATIONS: The results support basic principles of occupational therapy by highlighting important mediating roles of activity frequency and activity significance in reducing depressive symptoms. Understanding of these change mechanisms can help optimize activity-centered interventions to reduce depressive symptoms.
Cogan, A. M., Blanchard, J., Garber, S. L., Vigen, C. L., Carlson, M., & Clark, F. A. (2016). Systematic review of behavioral and educational interventions to prevent pressure ulcers in adults with spinal cord injury. Clinical Rehabilitation, pii:0269215516660855. Advance online publication. Link to full text Abstract →
OBJECTIVE: To investigate the efficacy of behavioral or educational interventions in preventing pressure ulcers in community-dwelling adults with spinal cord injury (SCI).
DATA SOURCES: Cochrane, Clinical Trials, PubMed, and Web of Science were searched in June 2016. The search combined related terms for pressure ulcers, spinal cord injury, and behavioral intervention. Each database was searched from its inception with no restrictions on year of publication.
REVIEW METHODS: Inclusion criteria required that articles were (a) published in a peer-reviewed journal in English, (b) evaluated a behavioral or educational intervention for pressure ulcer prevention, (c) included community-dwelling adult participants aged 18 years and older with SCI, (d) measured pressure ulcer occurrence, recurrence, or skin breakdown as an outcome, and (e) had a minimum of 10 participants. All study designs were considered. Two reviewers independently screened titles and abstracts. Extracted information included study design, sample size, description of the intervention and control condition, pressure ulcer outcome measures, and corresponding results.
RESULTS: The search strategy yielded 444 unique articles of which five met inclusion criteria. Three were randomized trials and two were quasi-experimental designs. A total of 513 participants were represented. The method of pressure ulcer or skin breakdown measurement varied widely among studies. Results on pressure ulcer outcomes were null in all studies. Considerable methodological problems with recruitment, intervention fidelity, and participant adherence were reported.
CONCLUSIONS: At present, there is no positive evidence to support the efficacy of behavioral or educational interventions in preventing pressure ulcer occurrence in adults with SCI.
Leland, N. E., Fogelberg, D., Sleight, A., Mallinson, T., Vigen, C., Blanchard, J., Carlson, M., & Clark, F. (2016). Napping and nighttime sleep: Findings from an occupation-based intervention. American Journal of Occupational Therapy, 70, 7004270010p1-7. http://dx.doi.org/10.5014/ajot.2016.017657. Link to full text Abstract →
OBJECTIVE: To describe sleeping behaviors and trends over time among an ethnically diverse group of community-living older adults.
METHOD: A descriptive secondary data analysis of a subsample (n = 217) from the Lifestyle Redesign randomized controlled trial was done to explore baseline napping and sleeping patterns as well as 6-mo changes in these outcomes.
RESULTS: At baseline, the average time sleeping was 8.2 hr daily (standard deviation = 1.7). Among all participants, 29% reported daytime napping at baseline, of which 36% no longer napped at follow-up. Among participants who stopped napping, those who received an occupation-based intervention (n = 98) replaced napping time with nighttime sleep, and those not receiving an intervention (n = 119) experienced a net loss of total sleep (p < .05).
CONCLUSION: Among participants who stopped napping, the occupation-based intervention may be related to enhanced sleep. More research examining the role of occupation-based interventions in improving sleep is warranted.
Schepens Niemiec, S. L., Carlson, M., Martinez, J., Guzman, L., Mahajan, A., & Clark, F. (2015). Developing occupation-based preventive programs for late-middle-aged Latino patients in safety-net health systems. American Journal of Occupational Therapy, 69, 6906240010p1-6906240010p11. http://dx.doi.org/10.5014/ajot.2015.015958. Link to full text Abstract →
Latino adults between ages 50 and 60 yr are at high risk for developing chronic conditions that can lead to early disability. We conducted a qualitative pilot study with 11 Latinos in this demographic group to develop a foundational schema for the design of health promotion programs that could be implemented by occupational therapy practitioners in primary care settings for this population. One-on-one interviews addressing routines and activities, health management, and health care utilization were conducted, audiotaped, and transcribed. Results of a content analysis of the qualitative data revealed the following six domains of most concern: Weight Management; Disease Management; Mental Health and Well-Being; Personal Finances; Family, Friends, and Community; and Stress Management. A typology of perceived health-actualizing strategies was derived for each domain. This schema can be used by occupational therapy practitioners to inform the development of health-promotion lifestyle interventions designed specifically for late-middle-aged Latinos.
Clark, F., Pyatak, E. A., Carlson, M., Blanche, E. I., Vigen, C., Hay, J., Mallinson, T., Blanchard, J., Unger, J. B., Garber, S. L., Diaz, J., Florindez, L. I., Atkins, M., Rubayi, S., & Azen, S. P. (2014). Implementing trials of complex interventions in community settings: The USC-Rancho Los Amigos Pressure Ulcer Prevention Study (PUPS). Clinical Trials, 11, 218-229. http://dx.doi.org/10.1177/1740774514521904. Link to full text Abstract →
BACKGROUND: Randomized trials of complex, non-pharmacologic interventions implemented in home and community settings, such as the University of Southern California (USC)-Rancho Los Amigos National Rehabilitation Center (RLANRC) Pressure Ulcer Prevention Study (PUPS), present unique challenges with respect to (1) participant recruitment and retention, (2) intervention delivery and fidelity, (3) randomization and assessment, and (4) potential inadvertent treatment effects.
PURPOSE: We describe the methods employed to address the challenges confronted in implementing PUPS. In this randomized controlled trial, we are assessing the efficacy of a complex, preventive intervention in reducing the incidence of, and costs associated with, the development of medically serious pressure ulcers in people with spinal cord injury.
METHODS: Individuals with spinal cord injury recruited from RLANRC were assigned to either a 12-month preventive intervention group or a standard care control group. The primary outcome is the incidence of serious pressure ulcers with secondary endpoints including ulcer-related surgeries, medical treatment costs, and quality of life. These outcomes are assessed at 12 and 24 months after randomization. Additionally, we are studying the mediating mechanisms that account for intervention outcomes.
RESULTS: PUPS has been successfully implemented, including recruitment of the target sample size of 170 participants, assurance of the integrity of intervention protocol delivery with an average 90% treatment adherence rate, and enactment of the assessment plan. However, implementation has been replete with challenges. To meet recruitment goals, we instituted a five-pronged approach customized for an underserved, ethnically diverse population. In intervention delivery, we increased staff time to overcome economic and cultural barriers to retention and adherence. To ensure treatment fidelity and replicability, we monitored intervention protocol delivery in accordance with a rigorous plan. Finally, we have overcome unanticipated assessment and design concerns related to (1) determining pressure ulcer incidence/severity, (2) randomization imbalance, and (3) inadvertent potential control group contamination.
LIMITATIONS: We have addressed the most daunting challenges encountered in the recruitment, assessment, and intervention phases of PUPS. Some challenges and solutions may not apply to trials conducted in other settings.
CONCLUSIONS: Overcoming challenges has required a multifaceted approach incorporating individualization, flexibility, and persistence, as well as the ability to implement needed mid-course corrections.
Carlson, M., Jackson, J., Mandel, D., Blanchard, J., Holguin, J., Lai, M. Y., Marterella, A., Vigen, C., Gleason, S., Lam, C., Azen, S., & Clark, F. (2014). Predictors of retention among African American and Hispanic older adult research participants in the Well Elderly 2 randomized controlled trial. Journal of Applied Gerontology, 33, 357-382. http://dx.doi.org/10.1177/0733464812471444. Link to full text Abstract →
The purpose of this study was to document predictors of long-term retention among minority participants in the Well Elderly 2 Study, a randomized controlled trial of a lifestyle intervention for community-dwelling older adults. The primary sample included 149 African American and 92 Hispanic men and women aged 60 to 95 years, recruited at senior activity centers and senior residences. Chi-square and logistic regression procedures were undertaken to examine study-based, psychosocial and health-related predictors of retention at 18 months following study entry. For both African Americans and Hispanics, intervention adherence was the strongest predictor. Retention was also related to high active coping and average (vs. high or low) levels of activity participation among African Americans and high social network strength among Hispanics. The results suggest that improved knowledge of the predictors of retention among minority elders can spawn new retention strategies that can be applied at individual, subgroup, and sample-wide levels.
Mallinson, T., Schepens Niemiec, S. L., Carlson, M., Leland, N., Vigen, C., Blanchard, J., & Clark, F. (2014). Development and validation of the activity significance personal evaluation (ASPEn) scale. Australian Occupational Therapy Journal, 61, 384-393. http://dx.doi.org/10.1111/1440-1630.12155. Link to full text Abstract →
BACKGROUND/AIM: Engagement in desired occupations can promote health and wellbeing in older adults. Assessments of engagement often measure frequency, amount or importance of specific activities. This study aimed to develop a scale to measure older adults' evaluation of the extent to which their everyday activities are contributing to their health and wellness.
METHODS: Eighteen items, each scored with a seven-point rating scale, were initially developed by content experts, covering perceptions of how daily activities contribute to physical and mental health, as well as satisfaction and activity participation in the last six months. Rasch analysis methods were used to refine the scale using the pencil and paper responses of 460 community-living older adults.
RESULTS: Initial Rasch analysis indicated three unlabelled rating scale categories were seldom used, reducing measurement precision. Five items were conceptually different by misfit statistics and principal component analysis. Subsequently, those items were removed and the number of rating scale steps reduced to 4. The remaining 13-item, 4-step scale, termed the Activity Significance Personal Evaluation (ASPEn), formed a unidimensional hierarchy with good fit statistics and targeting. Person separation reliability (2.7) and internal consistency (.91) indicated the tool is appropriate for individual person measurement. Relative validity indicated equivalence between Rasch measures and total raw scores.
CONCLUSIONS: ASPEn is a brief, easily administered assessment of older adults' perception of the contribution of everyday activities to personal health and wellness. ASPEn may facilitate occupational therapy practice by enabling clinicians to assess change in meaning of an older adult's activity over time.
Wilcox, R. R., Erceg-Hurn, D. M., Clark, F., & Carlson, M. (2014). Comparing two independent groups via the lower and upper quantiles. Journal of Statistical Computation and Simulation, 84, 1543-1551. http://dx.doi.org/10.1080/00949655.2012.754026. Link to full text Abstract →
The most common strategy for comparing two independent groups is in terms of some measure of location intended to reflect the typical observation. However, it can be informative and important to compare the lower and upper quantiles as well, but when there are tied values, extant techniques suffer from practical concerns reviewed in the paper. For the special case where the goal is to compare the medians, a slight generalization of the percentile bootstrap method performs well in terms of controlling Type I errors when there are tied values [Wilcox RR. Comparing medians. Comput. Statist. Data Anal. 2006;51:1934–1943]. But our results indicate that when the goal is to compare the quartiles, or quantiles close to zero or one, this approach is highly unsatisfactory when the quantiles are estimated using a single order statistic or a weighted average of two order statistics. The main result in this paper is that when using the Harrell–Davis estimator, which uses all of the order statistics to estimate a quantile, control over the Type I error probability can be achieved in simulations, even when there are tied values, provided the sample sizes are not too small. It is demonstrated that this method can also have substantially higher power than the distribution free method derived by Doksum and Sievers [Plotting with confidence: graphical comparisons of two populations. Biometrika 1976;63:421–434]. Data from two studies are used to illustrate the practical advantages of the method studied here.
Wilcox, R. R., Carlson, M. E., Azen, S. P., & Clark, F. A. (2013). Avoid lost discoveries, because of violations of standard assumptions, by using modern robust statistical methods. Journal of Clinical Epidemiology, 66, 319-329. http://dx.doi.org/10.1016/j.jclinepi.2012.09.003. Link to full text Abstract →
OBJECTIVES: Recently, there have been major advances in statistical techniques for assessing central tendency and measures of association. The practical utility of modern methods has been documented extensively in the statistics literature, but they remain underused and relatively unknown in clinical trials. Our objective was to address this issue.
STUDY DESIGN AND PURPOSE: The first purpose was to review common problems associated with standard methodologies (low power, lack of control over type I errors, and incorrect assessments of the strength of the association). The second purpose was to summarize some modern methods that can be used to circumvent such problems. The third purpose was to illustrate the practical utility of modern robust methods using data from the Well Elderly 2 randomized controlled trial.
RESULTS: In multiple instances, robust methods uncovered differences among groups and associations among variables that were not detected by classic techniques. In particular, the results demonstrated that details of the nature and strength of the association were sometimes overlooked when using ordinary least squares regression and Pearson correlation.
CONCLUSION: Modern robust methods can make a practical difference in detecting and describing differences between groups and associations between variables. Such procedures should be applied more frequently when analyzing trial-based data.
Carlson, M., Kuo, A., Chou, C., & Clark, F. (2013). Relationship of global self-evaluations of activity to psychosocial and health-related aging outcomes. OTJR: Occupation, Participation, and Health, 33, 180-189. http://dx.doi.org/10.3928/15394492-20130712-01. Link to full text Abstract →
The authors obtained older adults’ self-rated judgments about the quality of their activity engagement considered as a whole (global activity evaluation) and, using cross-sectional survey data, tested the ability of such judgments to predict well-being. Participants were 460 community-dwelling older adults who responded to (1) global activity evaluations, (2) activity participation frequency scales, and (3) indices of life satisfaction, depression, and physical and mental health-related quality of life. Regression analyses indicated that global activity evaluations had a stronger relationship to psychosocial outcome indices than did participation frequency ratings, although both measurement approaches were associated with statistically significant predictions. However, global evaluations and participation frequency ratings were approximately equal in their ability to predict physical health-related quality of life. These relationships were fairly consistent across ethnic groups. Overall, the results suggest that ideally the two strategies for assessing activity should be incorporated in future research on activity and occupational therapy practice.
Clark, F. A., Jackson, J. M., Carlson, M. E., Chou, C. P., Cherry, B. J., Jordan-Marsh, M., Knight, B. G., Mandel, D., Blanchard, J., Granger, D. A., Wilcox, R. R., Lai, M. Y., White, B. A., Hay, J. W., Lam, C., Marterella, A., & Azen, S. P. (2012). Effectiveness of a lifestyle intervention in promoting the well-being of independently living older people: Results of the Well Elderly 2 Randomised Controlled Trial. Journal of Epidemiology and Community Health, 66, 782-790. http://dx.doi.org/10.1136/jech.2009.099754. Link to full text Abstract →
BACKGROUND: Older people are at risk for health decline and loss of independence. Lifestyle interventions offer potential for reducing such negative outcomes. The aim of this study was to determine the effectiveness and cost-effectiveness of a preventive lifestyle-based occupational therapy intervention, administered in a variety of community-based sites, in improving mental and physical well-being and cognitive functioning in ethnically diverse older people.
METHODS: A randomised controlled trial was conducted comparing an occupational therapy intervention and a no-treatment control condition over a 6-month experimental phase. Participants included 460 men and women aged 60-95 years (mean age 74.9±7.7 years; 53% <$12,000 annual income) recruited from 21 sites in the greater Los Angeles metropolitan area.
RESULTS: Intervention participants, relative to untreated controls, showed more favourable change scores on indices of bodily pain, vitality, social functioning, mental health, composite mental functioning, life satisfaction and depressive symptomatology (ps<0.05). The intervention group had a significantly greater increment in quality-adjusted life years (p<0.02), which was achieved cost-effectively (US $41,218/UK £24,868 per unit). No intervention effect was found for cognitive functioning outcome measures.
CONCLUSIONS: A lifestyle-oriented occupational therapy intervention has beneficial effects for ethnically diverse older people recruited from a wide array of community settings. Because the intervention is cost-effective and is applicable on a wide-scale basis, it has the potential to help reduce health decline and promote well-being in older people.
Carlson, M., Park, D. J., Kuo, A., & Clark, F. (2012). Occupation in relation to the self. Journal of Occupational Science, http://dx.doi.org/10.1080/14427591.2012.727356. Link to full text Abstract →
Knowledge of the construct of occupation remains fragmented within traditional social science disciplines. In this paper, we aim to provide a theoretical synthesis by explicating the unique properties of occupation in relation to the self within social science discourse. Occupations relate to other social science constructs in three ways: (a) they recruit a set of associated changes into a person's life; (b) they serve a person's ability to achieve important goals; and (c) they act as a mirror by reflecting multiple dimensions of the self. Key characteristics of occupation such as its experiential salience and its repetitional flavor powerfully amplify its significant role in affecting self-relevant outcomes. Occupation represents a crucial playing field that profoundly affects the unfolding of human lives. Therefore, the continued pursuit of occupational science is warranted and can uniquely contribute to an improved understanding of the self.
Carlson, M. E., Wilcox, R. R., Chou, C. P., Chang, M., Yang, F., Blanchard, J., Marterella, A., Kuo, A., & Clark, F. A. (2011). Psychometric properties of reverse-scored items on the CES-D in a sample of ethnically diverse older adults. Psychological Assessment, 23, 558-562. http://dx.doi.org/10.1037/a0022484. Link to full text Abstract →
Reverse-scored items on assessment scales increase cognitive processing demands and may therefore lead to measurement problems for older adult respondents. In this study, the objective was to examine possible psychometric inadequacies of reverse-scored items on the Center for Epidemiologic Studies Depression Scale (CES-D) when used to assess ethnically diverse older adults. Using baseline data from a gerontologic clinical trial (n = 460), we tested the hypotheses that the reversed items on the CES-D (a) are less reliable than nonreversed items, (b) disproportionately lead to intraindividually atypical responses that are psychometrically problematic, and (c) evidence improved measurement properties when an imputation procedure based on the scale mean is used to replace atypical responses. In general, the results supported the hypotheses. Relative to nonreversed CES-D items, the 4 reversed items were less internally consistent, were associated with lower item-scale correlations, and were more often answered atypically at an intraindividual level. Further, the atypical responses were negatively correlated with responses to psychometrically sound nonreversed items that had similar content. The use of imputation to replace atypical responses enhanced the predictive validity of the set of reverse-scored items. Among older adult respondents, reverse-scored items are associated with measurement difficulties. It is recommended that appropriate correction procedures such as item readministration or statistical imputation be applied to reduce the difficulties.
Blanche, E. J., Fogelberg, D., Diaz, J., Carlson, M. E., & Clark, F. A. (2011). Manualization of occupational therapy interventions: Illustrations from the Pressure Ulcer Prevention Research Program. American Journal of Occupational Therapy, 65, 711-719. http://dx.doi.org/10.5014/ajot.2011.001172. Link to full text Abstract →
The manualization of a complex occupational therapy intervention is a crucial step in ensuring treatment fidelity for both clinical application and research purposes. Toward the latter end, intervention manuals are essential for ensuring trustworthiness and replicability of randomized controlled trials that aim to provide evidence of the effectiveness of occupational therapy. In this article, we review the literature on the process of intervention manualization. We then illustrate the prescribed steps through our experience in implementing the University of Southern California/Rancho Los Amigos National Rehabilitation Center's collaborative Pressure Ulcer Prevention Project. In this research program, qualitative research provided the initial foundation for manualization of a multifaceted occupational therapy intervention designed to reduce the incidence of medically serious pressure ulcers in adults with spinal cord injury.
Vaishampayan, A., Clark, F. A., Carlson, M. E., & Blanche, E. J. (2011). Preventing pressure ulcers in people with spinal cord injury: Targeting risky life circumstances through a community-based interventions. Advances in Skin and Wound Care, 24, 275-284. http://dx.doi.org/10.1097/01.ASW.0000398663.66530.46. Link to full text Abstract →
OBJECTIVE: The objectives of the study were to sensitize practitioners working with individuals with spinal cord injury (SCI) to the complex life circumstances that are implicated in the development of pressure ulcers (PrUs) and to document the ways that interventions can be adapted to target individual needs.
METHODS: This study was a content analysis of weekly fidelity/quality control meetings that were undertaken as part of a lifestyle intervention for PrU prevention in community-dwelling adults with SCI.
RESULTS: Four types of lifestyle-relevant challenges to ulcer prevention were identified: risk-elevating life circumstances, communication difficulties, equipment problems, and individual personality issues. Intervention flexibility was achieved by changing the order of treatment modules, altering the intervention content or delivery approach, or going beyond the stipulated content.
CONCLUSION: Attention to recurrent types of individual needs, along with explicit strategies for tailoring interventions published in a manual, has the potential to enhance PrU prevention efforts for adults with SCI.
Werner, J. M., Carlson, M. E., Jordan-Marsh, M., & Clark, F. A. (2011). Predictors of computer use in community-dwelling, ethnically diverse older adults. Human Factors, 53, 431-447. http://dx.doi.org/10.1177/0018720811420840. Link to full text Abstract →
OBJECTIVE: In this study, we analyzed self-reported computer use, demographic variables, psychosocial variables, and health and well-being variables collected from 460 ethnically diverse, community-dwelling elders to investigate the relationship computer use has with demographics, well-being, and other key psychosocial variables in older adults.
BACKGROUND: Although younger elders with more education, those who employ active coping strategies, or those who are low in anxiety levels are thought to use computers at higher rates than do others, previous research has produced mixed or inconclusive results regarding ethnic, gender, and psychological factors or has concentrated on computer-specific psychological factors only (e.g., computer anxiety). Few such studies have employed large sample sizes or have focused on ethnically diverse populations of community-dwelling elders.
METHOD: With a large number of overlapping predictors, zero-order analysis alone is poorly equipped to identify variables that are independently associated with computer use. Accordingly, both zero-order and stepwise logistic regression analyses were conducted to determine the correlates of two types of computer use: e-mail and general computer use.
RESULTS: Results indicate that younger age, greater level of education, non-Hispanic ethnicity, behaviorally active coping style, general physical health, and role-related emotional health each independently predicted computer usage.
CONCLUSION: Study findings highlight differences in computer usage, especially in regard to Hispanic ethnicity and specific health and well-being factors.
APPLICATION: Potential applications of this research include future intervention studies, individualized computer-based activity programming, or customizable software and user interface design for older adults responsive to a variety of personal characteristics and capabilities.
Jackson, J. M., Carlson, M. E., Rubayi, S., Scott, M. D., Atkins, M. S., Blanche, E. J., Saunders-Newton, C. D., Mielke, S. E., Wolfe, M. K., & Clark, F. A. (2010). Qualitative study of principles pertaining to lifestyle and pressure ulcer risk in adults with spinal cord injury. Disability and Rehabilitation, 32, 567-578. http://dx.doi.org/10.3109/09638280903183829. Link to full text Abstract →
PURPOSE: The aim of this article is to identify overarching principles that explain how daily lifestyle considerations affect pressure ulcer development as perceived by adults with spinal cord injury (SCI).
METHOD: Qualitative in-depth interviews over an 18-month period with 20 adults with spinal injury and a history of pressure ulcers were conducted using narrative and thematic analyses.
RESULTS: Eight complexly interrelated daily lifestyle principles that explain pressure ulcer development were identified: perpetual danger; change/disruption of routine; decay of prevention behaviors; lifestyle risk ratio; individualization; simultaneous presence of prevention awareness and motivation; lifestyle trade-off; and access to needed care, services and supports.
CONCLUSIONS: Principles pertaining to the relationship between in-context lifestyle and pressure ulcer risk underscore previous quantitative findings, but also lead to new understandings of how risk unfolds in everyday life situations. Pressure ulcer prevention for community-dwelling adults with SCI can potentially be enhanced by incorporating principles, such as the decay of prevention behaviors or lifestyle trade-off, that highlight special patterns indicative of elevated risk. The identified principles can be used to theoretically drive future research or to guide innovative lifestyle-focused intervention approaches. Public policies that promote short-term preventive interventions at critical junctures throughout a person's life should be considered.
Eakman, A. M., Carlson, M. E., & Clark, F. A. (2010). Factor structure, reliability, and convergent validity of the Engagement in Meaningful Activities Survey for older adults. OTJR: Occupation, Participation and Health, 30, 111-121. http://dx.doi.org/10.3928/15394492-20090518-01. Link to full text Abstract →
This study evaluated the psychometric properties of the Engagement in Meaningful Activities Survey (EMAS) (Goldberg, Brintnell, & Goldberg, 2002) in a sample of older adults living in the greater Los Angeles area. The EMAS evidenced moderate test-retest reliability (r = .56) and good internal consistency (α = .89). Exploratory factor analysis (principal components) discerned a two-component structure within the EMAS, indicative of Personal-Competence and Social-Experiential meaning. The EMAS demonstrated theoretically predicted zero-order correlations with measures of meaning and purpose in life, depressive symptomology, life satisfaction, and health-related quality of life. Regression analyses discerned that purpose and meaning in life consistently predicted the EMAS and its components. Furthermore, individuals reporting greater levels of Social-Experiential relative to Personal-Competence meaning had the lowest levels of physical health-related quality of life. This study offers initial evidence in support of the EMAS as a valid measure of meaningful activity in older adults.
Eakman, A. M., Carlson, M. E., & Clark, F. A. (2010). The Meaningful Activity Participation Assessment: A measure of engagement in personally valued activities. International Journal of Aging and Human Development, 70, 299-317. http://dx.doi.org/10.2190/AG.70.4.b. Link to full text Abstract →
The Meaningful Activity Participation Assessment (MAPA), a recently developed 28-item tool designed to measure the meaningfulness of activity, was tested in a sample of 154 older adults. The MAPA evidenced a sufficient level of internal consistency and test-retest reliability and correlated as theoretically predicted with the Life Satisfaction Index-Z, the Satisfaction with Life Scale, the Engagement in Meaningful Activities Survey, the Purpose in Life Test, the Center for Epidemiologic Studies Depression Inventory and the Rand SF-36v2 Health Survey subscales. Zero-order correlations consistently demonstrated meaningful relationships between the MAPA and scales of psychosocial well-being and health-related quality of life. Results from multiple regression analyses further substantiated these findings, as greater meaningful activity participation was associated with better psychological well-being and health-related quality of life. The MAPA appears to be a reliable and valid measure of meaningful activity, incorporating both subjective and objective indicators of activity engagement.
Fogelberg, D., Atkins, M., Blanche, E. J., Carlson, M. E., & Clark, F. A. (2009). Decisions and dilemmas in everyday life: Daily use of wheelchairs by individuals with spinal cord injury and the impact on pressure ulcer risk. Topics in Spinal Cord Injury Rehabilitation, 15(2), 16-32. http://dx.doi.org/10.1310/sci1502-16. Link to full text Abstract →
Individuals with spinal cord injury (SCI) use wheelchairs for mobility and for full participation in their daily activities. The use of wheelchairs, however, can increase the risk of pressure ulcers. This study focused on wheelchair users’ perceptions of the interplay between their wheeled mobility and the development of pressure ulcers by performing a secondary analysis of data gathered during a 2-year ethnographic study of 20 community-dwelling adults with SCI. Data from a subset of these individuals are described; each of these stories contains a pressure ulcer risk episode related to wheeled mobility or cushion use. Identified risk episodes were associated with wheelchair selection, wheelchair adjustment, habituation to new equipment, lifestyle choices, and challenging life contexts. Examples highlighted the crucial relationship between individuals’ minute-to-minute decision-making and pressure ulcer risk.
Dunn, C. A., Carlson, M. E., Jackson, J. M., & Clark, F. A. (2009). Response factors surrounding progression of pressure ulcers in community-residing adults with spinal cord injury. American Journal of Occupational Therapy, 63, 301-309. http://dx.doi.org/10.5014/ajot.63.3.301. Link to full text Abstract →
OBJECTIVE: This study examined how community-dwelling adults with spinal cord injury (SCI) respond in real-life circumstances after detecting a low-grade (Stage 1 or Stage 2) pressure ulcer.
METHOD: We performed a secondary analysis of personal information profiles obtained in a previous qualitative research study. Profiles were examined to explore how individualized lifestyle considerations affected pressure ulcer risk in 19 adults with SCI who responded to an early ulcer that later progressed to a medically serious level.
RESULTS: On the basis of a total of 46 pressure ulcer events, we identified a typological framework that described eight primary response categories and seven subcategories.
CONCLUSION: The findings have significant practice implications for occupational therapists who provide services for adults with SCI living in the community. The importance of combining an initial individualized preventive intervention with structured follow-up within a person’s unique everyday life setting is further explored.
Jackson, J. M., Mandel, D., Blanchard, J., Carlson, M. E., Cherry, B. J., Azen, S. P., Chou, C. P., Jordan-Marsh, M., Forman, T., White, B. A., Granger, D., Knight, B. G., & Clark, F. A. (2009). Confronting challenges in intervention research with ethnically diverse older adults: The USC Well Elderly II Trial. Clinical Trials, 6, 90-101. http://dx.doi.org/10.1177/1740774508101191. Link to full text Abstract →
BACKGROUND: Community-dwelling older adults are at risk for declines in physical health, cognition, and psychosocial well-being. However, their enactment of active and health-promoting lifestyles can reduce such declines.
PURPOSE: The purpose of this article is to describe the USC Well Elderly II study, a randomized clinical trial designed to test the effectiveness of a healthy lifestyle program for elders, and document how various methodological challenges were addressed during the course of the trial.
METHODS: In the study, 460 ethnically diverse elders recruited from a variety of sites in the urban Los Angeles area were enrolled in a randomized experiment involving a crossover design component. Within either the first or second 6-month phase of their study involvement, each elder received a lifestyle intervention designed to improve a variety of aging outcomes. At 4-5 time points over an 18-24 month interval, the research participants were assessed on measures of healthy activity, coping, social support, perceived control, stress-related biomarkers, perceived physical health, psychosocial well-being, and cognitive functioning to test the effectiveness of the intervention and document the process mechanisms responsible for its effects.
RESULTS: The study protocol was successfully implemented, including the enrollment of study sites, the recruitment of 460 older adults, administration of the intervention, adherence to the plan for assessment, and establishment of a large computerized data base.
LIMITATIONS: Methodological challenges were encountered in the areas of site recruitment, participant recruitment, testing, and intervention delivery.
CONCLUSIONS: The completion of clinical trials involving elders from numerous local sites requires careful oversight and anticipation of threats to the study design that stem from: (a) social situations that are particular to specific study sites; and (b) physical, functional, and social challenges pertaining to the elder population.
During the past century, numerous researchers and theorists have argued that human lives are largely shaped by the nonreflective realm of habit. Beyond this observation, however, scholarly conceptualizations of habit are widely divergent, ranging from neural-level to culturally saturated macro-level constructs. To clarify the multiple ways that habit has been construed and is related to rehabilitation, the authors present a typology of nine categories of habits: habit as tic; habit as neural networks; habit as conditioned responses; habit as addiction; habit as single, everyday activities; habit as routine; habit as custom, ritual, rite, or ceremony; habit as character; and habit as habitus. Although these categories overlap and share common properties, their conceptual features differ along several dimensions. Each category offers a distinct perspective from which to understand the role of habit in the lives of clients undergoing rehabilitation, which the authors illustrate using examples from the Pressure Ulcer Prevention Study (PUPS), a qualitative study on the contextual factors that lead to serious recurrent pressure ulcers in people with spinal cord injuries. The authors argue that habit is a ubiquitous, protean force that presents itself in many interlinking forms, steering the course of human lives in both health-promoting and destructive directions. To have the greatest effect on health and participation, rehabilitation professionals must examine the nuanced ways that habit may operate both in the lives of clients and in professional practice.
Clark, F. A., Jackson, J. M., Scott, M. D., Carlson, M. E., Atkins, M. S., Uhles-Tanaka, D., & Rubayi, S. (2006). Data-based models of how pressure ulcers develop in daily-living contexts of adults with spinal cord injury. Archives of Physical Medicine and Rehabilitation, 87, 1516-1525. http://dx.doi.org/10.1016/j.apmr.2006.08.329. Link to full text Abstract →
OBJECTIVE: To examine the daily-lifestyle influences on the development of pressure ulcers in adults with spinal cord injury (SCI).
DESIGN: Qualitative investigation using in-depth interviewing and participant observation.
SETTING: Participants were studied in their homes and other naturalistic contexts.
PARTICIPANTS: Twenty men and women of diverse ethnicities with paraplegia or tetraplegia who were recruited at a pressure ulcer management clinic in a large rehabilitation facility.
INTERVENTIONS: Not applicable.
MAIN OUTCOME MEASURES: Detailed descriptive information pertaining to the development of recurring pressure ulcers in relation to participants' daily routine and activity, personal choices, motivating influences, lifestyle challenges, and prevention techniques and strategies.
RESULTS: The daily-lifestyle influences on pressure ulcer development in adults with SCI can be described through various models that vary in complexity, depending on whether they incorporate individualization, interrelations among modeled elements, situational specificity, and/or temporal comprehensiveness. Ulcers are most likely to develop when a person with a relatively high-risk background profile is exposed to an equilibrium-disrupting change event that culminates in a specific pressure ulcer risk episode.
CONCLUSIONS: The results underscore the significant degree of complexity and individualization that characterize the emergence of pressure ulcers in daily-life contexts. Prevention efforts should therefore incorporate attention to the unique constellation of circumstances that comprise a person's everyday life.
Hay, J., LaBree, L., Luo, R., Clark, F. A., Carlson, M. E., Mandel, D., Zemke, R., Jackson, J. M., & Azen, S. P. (2002). Cost-effectiveness of preventive occupational therapy for independent-living older adults. Journal of the American Geriatrics Society, 50, 1381-1388. http://dx.doi.org/10.1046/j.1532-5415.2002.50359.x. Link to full text Abstract →
OBJECTIVES: To evaluate the cost-effectiveness of a 9-month preventive occupational therapy (OT) program in the Well-Elderly Study: a randomized trial in independent-living older adults that found significant health, function, and quality of life benefits attributable to preventive OT.
DESIGN: A randomized trial.
SETTING: Two government-subsidized apartment complexes.
PARTICIPANTS: One hundred sixty-three culturally diverse volunteers aged 60 and older.
INTERVENTION: An OT group, a social activity group (active control), and a nontreatment group (passive control).
MEASUREMENTS: Use of healthcare services was determined by telephone interview during and after the treatment phase. A conversion algorithm was applied to the RAND 36-item Short Form Health Survey to derive a preference-based health-related quality of life index, quality-adjusted life years (QALYs), and the incremental cost-effectiveness ratio for preventive OT relative to the combined control group.
RESULTS: Costs for the 9-month OT program averaged $548 per subject. Postintervention healthcare costs were lower for the OT group ($967) than for the active control group ($1,726), the passive control group ($3,334), or a combination of the control groups ($2,593). The quality of life index showed a 4.5% QALY differential (OT vs combined control), P < .001. The cost per QALY estimates for the OT group was $10,666 (95% confidence interval = $6,747–$25,430). For the passive and active control groups, the corresponding costs per QALY were $13,784 and $7,820, respectively.
CONCLUSION: In this study, preventive OT demonstrated cost-effectiveness in conjunction with a trend toward decreased medical expenditures.
Clark, F. A., Rubayi, S., Jackson, J. M., Uhles-Tanaka, D., Scott, M., Atkins, M., Gross, K. A., & Carlson, M. E. (2001). The role of daily activities in pressure ulcer development [Guest editorial]. Advances in Skin & Wound Care, 14, 52-54. Link to full text Abstract →
Pressure ulcers are a serious complication of spinal cord injury (SCI). Although pressure ulcers are often assumed to be preventable, research suggests that more than three fourths of individuals with an SCI will develop a pressure ulcer over the course of their lifetime. The total annual cost to treat these ulcers is nearly $1.5 billion.1-3 Not only can pressure ulcers be potentially life-threatening, but they can also impede the rehabilitation process and significantly disrupt the quality of life of persons with an SCI.
Because the pressure ulcer problem among persons with an SCI is so severe, it is important for clinicians to develop a full understanding of the underlying contributing factors in attempting to reduce pressure ulcer risk. Research has demonstrated that in the realm of lifestyle choices, factors such as poor fitness, inadequate nutrition, unemployment, decreased social involvement, substance abuse, and emotional stress can increase the risk for developing pressure ulcers. By focusing on generalizable quantitative relationships between variables, these researchers have demonstrated that, on average, individuals with an SCI who manifest a particular risk factor have a greater likelihood of developing a pressure ulcer.
Clark, F. A., Azen, S. P., Carlson, M. E., Mandel, D., LaBree, L., Hay, J., Zemke, R., Jackson, J. M., & Lipson, L. (2001). Embedding health-promoting changes into the daily lives of independent-living older adults: Long-term follow-up of occupational therapy intervention. Journals of Gerontology: Series B, Psychological Sciences and Social Sciences, 56, P60-P63. http://dx.doi.org/10.1093/geronb/56.1.P60. Link to full text Abstract →
The Well Elderly Study was a randomized trial in independent-living older adults that found significant health, function, and quality of life benefits attributable to a 9-month program in preventive occupational therapy (OT). All participants completing the trial were followed for an additional 6 months without further intervention and then reevaluated using the same battery of instruments. Long-term benefit attributable to preventive OT was found for the quality of interaction scale of the Functional Status Questionnaire and for six of eight scales on the RAND SF-36: physical functioning, role functioning, vitality, social functioning, role emotional, and general mental health (p < .05). Approximately 90% of the therapeutic gain observed following OT treatment was retained in follow-up. The finding of a sustained effect for preventive OT is of great public health relevance given the looming health care cost crisis associated with our nation's expanding elderly population.
Jackson, J. M., Kennedy, B. L., Mandel, D., Carlson, M. E., Cherry, B. J., Fanchiang, S. P., Ding, L., Zemke, R., Azen, S. P., LaBree, L., & Clark, F. A. (2000). Derivation and pilot assessment of a health promotion program for Mandarin-speaking Chinese older adults. The International Journal of Aging & Human Development, 50, 127-149. http://dx.doi.org/10.2190/9V9H-E4L7-BTJP-9WMJ. Link to full text Abstract →
As the percentage of older adults of diverse ethnicities increases in the United States, the call for culturally sensitive health care service strategies that target the special needs of older people grows. The present report describes methods used to adapt a health care program so that it would better meet the needs of a group of well, older Mandarin-speaking Chinese residents of Los Angeles. The specific qualitative research procedures that we used to adapt the treatment program are described, along with the particular adaptations that emerged. Additionally, outcomes from a randomized pilot experiment are presented that are consistent with the notion that the adapted program was effective in reducing health-related declines among older Mandarin-speaking men and women. The overall outcome of this project is in agreement with other reports in the health care literature that address the importance of providing culturally sensitive health care service for elders.
Azen, S. P., Palmer, J. M., Carlson, M. E., Mandel, D., Cherry, B. J., Fanchiang, S. P., Jackson, J. M., & Clark, F. A. (1999). Psychometric properties of a Chinese translation of the SF-36 Health Survey Questionnaire in the Well Elderly Study. Journal of Aging and Health, 11, 240-251. http://dx.doi.org/10.1177/089826439901100206. Link to full text Abstract →
OBJECTIVES: To evaluate the psychometric properties of a Chinese translation of the 36-item Short Form Health Survey (SF-36) in the Well Elderly Study—a randomized clinical trial designed to evaluate the effectiveness of preventive occupational therapy services specifically tailored for multiethnic, independent-living, older adults.
METHODS: Translation and back-translation procedures were used to obtain appropriate meanings for the SF-36 survey questions and to ensure face, functional, and conceptual equivalence.
RESULTS: Statistical analyses demonstrated satisfactory reliability and validity, with the results generally similar to those reported for older Anglo adults.
DISCUSSION: As the percentage of older adults of diverse ethnicity increases, the need for health care research and service strategies that can effectively include multiple ethnicities becomes paramount. The results of this study suggest that a Chinese-translated SF-36 can be used to assess multiple dimensions of health in a Mandarin-speaking population of older adults.
Carlson, M. E., Clark, F. A., & Young, B. (1998). Practical contributions of occupational science to the art of successful ageing: How to sculpt a meaningful life in older adulthood. Journal of Occupational Science, 5, 107-118. http://dx.doi.org/10.1080/14427591.1998.9686438. Link to full text Abstract →
Given that the longevity revolution has already arrived and will continue to flourish in the upcoming decades, Western societies are confronted with the urgent challenge of promoting the goal of successful ageing for untold millions of citizens. With regard to this goal, current thinking points to the optimistic conclusion that potentially controllable lifestyle factors play a crucial role in enabling people to experience health and satisfying lives well into older adulthood. In this paper, the importance of occupation as providing a fundamental, personally relevant context for the enactment of sustainable lifestyle choices that foster successful ageing is described. This stress on the significance of occupation is supported by the successful outcome of an experimental test of a preventive occupational therapy intervention designed to promote health and psychosocial well-being in community dwelling elders. Based on the theory and research that is discussed, a practically oriented synthetic overview is provided of the conditions conducive to successful ageing.
Jackson, J. M., Carlson, M. E., Mandel, D., Zemke, R., & Clark, F. A. (1998). Occupation in lifestyle redesign: The Well Elderly Study occupational therapy program. American Journal of Occupational Therapy, 52, 326-336. http://dx.doi.org/10.5014/ajot.52.5.326. Link to full text Abstract →
This article describes an innovative preventive occupational therapy intervention for well older adults, the Well Elderly Treatment Program. In a previously reported large-scale randomized effectiveness study, this intervention was found to be highly successful in enhancing the physical and mental health, occupational functioning, and life satisfaction of multicultural, community-dwelling elders. In this article, the philosophical background, manner of development, topical content, methods of program delivery, and mechanisms underlying the program's positive effects are discussed, along with implications for occupational therapy practice. The treatment was based on application of occupational science theory and research and emphasized the therapeutic process of lifestyle redesign in enabling the participants to actively and strategically select an individualized pattern of personally satisfying and health-promoting occupations. The wide-ranging effectiveness of the program supports the occupational therapy profession's emphasis on occupation in affecting health and positions practitioners to extend their services to the realm of preventive interventions.
Clark, F. A., Carlson, M. E., & Polkinghorne, D. E. (1997). The legitimacy of life history and narrative approaches in the study of occupation [The issue is]. American Journal of Occupational Therapy, 51, 313-317. http://dx.doi.org/10.5014/ajot.51.4.313. Link to full text Abstract →
In a recent article published in this column, Duchek and Thessing (1996) expressed their belief that the use of life history and narrarive as research methodologies will not "completely meet the objectives" (p. 395) of occupational science. We feel that it is important to respond to the issues they raise.
Clark, F. A., Azen, S. P., Zemke, R., Jackson, J. M., Carlson, M. E., Mandel, D., Hay, J., Josephson, K., Cherry, B., Hessel, C., Palmer, J., & Lipson, L. (1997). Occupational therapy for independent-living older adults: A randomized controlled trial. Journal of the American Medical Association, 278, 1321-1326. http://dx.doi.org/10.1001/jama.1997.03550160041036. Link to full text Abstract →
CONTEXT: Preventive health programs may mitigate against the health risks of older adulthood.
OBJECTIVE: To evaluate the effectiveness of preventive occupational therapy (OT) services specifically tailored for multiethnic, independent-living older adults. Design.-A randomized controlled trial.
SETTING: Two government subsidized apartment complexes for independent-living older adults.
SUBJECTS: A total of 361 culturally diverse volunteers aged 60 years or older.
INTERVENTION: An OT group, a social activity control group, and a nontreatment control group. The period of treatment was 9 months.
MAIN OUTCOME MEASURES: A battery of self-administered questionnaires designed to measure physical and social function, self-rated health, life satisfaction, and depressive symptoms.
RESULTS: Benefit attributable to OT treatment was found for the quality of interaction scale on the Functional Status Questionnaire (P=.03), Life Satisfaction Index-Z (P=.03), Medical Outcomes Study Health Perception Survey (P=.05), and for 7 of 8 scales on the RAND 36-Item Health Status Survey, Short Form: bodily pain (P=.03), physical functioning (P=.008), role limitations attributable to health problems (P=.02), vitality (P=.004), social functioning (P=.05), role limitations attributable to emotional problems (P=.05), and general mental health (P=.02).
CONCLUSIONS: Significant benefits for the OT preventive treatment group were found across various health, function, and quality-of-life domains. Because the control groups tended to decline over the study interval, our results suggest that preventive health programs based on OT may mitigate against the health risks of older adulthood.
Clark, F. A., Carlson, M. E., Zemke, R., Frank, G., Patterson, K., Ennevor, B. L., Rankin-Martinez, A., Hobson, L. A., Crandall, J., Mandel, D., & Lipson, L. (1996). Life domains and adaptive strategies of a group of low-income, well older adults. American Journal of Occupational Therapy, 50, 99-108. http://dx.doi.org/10.5014/ajot.50.2.99. Link to full text Abstract →
Older adults are at increased risk for a variety of physical and functional limitations that threaten their ability to lead independent and fulfilling lives. Consequently, they stand to benefit from personalized strategies of adaptation that enable them to achieve successful outcomes in their daily activities and desired goals. In the current investigation, a qualitative descriptive methodology was used to document the perceived life domain of importance and associated strategies of adaptation of 29 residents of Angelus Plaza, a federally subsidized apartment complex in downtown Los Angeles for low-income, well older adults. On the basis of interview data, 10 life domains were identified, and within each domain, a typology of adaptive strategies was derived. The domains were activities of daily living (ADL), adaptation to a multicultural environment, free time usage, grave illness and death–spirituality, health maintenance, mobility maintenance, personal finances, personal safety, psychological well-being and happiness, and relationships with others. Although the typology should not be generalized to a geriatric population, therapists may wish to refer to it to gain a sense of the extent to which certain adaptive strategies may be applicable to the lives of particular older adults to whom they deliver services. The teaching of these adaptive strategies could then be incorporated into an individualized treatment plan.
The typology also provides a broad picture of the kinds of adaptive strategies used by the older adults as a way of coping and adapting to their setting. Although some of the domains do not differ from those typically addressed in occupational therapy textbooks on geriatric care (e.g., ADL, health maintenance), others seem uniquely tailored to the specifics of the Angelus Plaza context (e.g., personal safety). Finally, certain domains emerged that may be highly relevant to older adults in most settings but are not typically the focus of occupational therapy programs (e.g., grave illness and death–spirituality, relationships with others). The emergence of these domains from our data suggests that therapists may wish to consider them more in treatment if they are convinced that they possess local relevance.
Baydur, A. N., & Carlson, M. E. (1996). Immediate response to inspiratory resistive loading in anesthetized patients with kyphoscoliosis: spirometric and neural effects. Lung, 174, 99-118. http://dx.doi.org/10.1007/BF00177704. Link to full text Abstract →
In kyphoscoliosis (KS), lung volumes are reduced, respiratory elastance and resistance are increased, and breathing pattern is rapid and shallow, attributes that may contribute to defense of tidal volume (VT) in the face of inspiratory resistive loading. The control of ventilation of 12 anesthetized patients about to undergo corrective spinal surgery was compared to that of 11 anesthetized patients free of cardiothoracic disease during quiet breathing and the first breath through one of three linear resistors. Mean forced vital capacity (FVC) of the KS group was 48% that of the controls (C). Passive elastance (Ers) and active elastance and resistance (Ers and Rrs, respectively) were computed according to previously described techniques (Behrakis PK, Higgs BD, Baydur A, Zin WA, Milic-Emili J (1983) Active inspiratory impedance in halothane-anesthetized humans. J Appl Physiol 54:1477–1481). Baseline tidal volume VT, inspiratory duration TI, expiratory duration TE, duration of total breathing cycle TT, and inspiratory duty cycle TI/TT were significantly reduced, while VE was slightly decreased in the KS. Ers, Ers, and Rrs, were, respectively, 72, 69, and 89% greater in the KS. Driving pressure (Pmus) was derived from the equation of motion, using active values of respiratory elastance. With resistive loading, there was greater prolongation of TI in the C, while percent reduction in VT and minute ventilation VE was less in KS. Compensation in both groups was achieved through three changes in the Pmus waveform. (1) Peak amplitude increased. (2) The duration of the rising phase increased. (3) The rising Pmus curve became more concave to the time axis. These changes were most marked with application of the highest resistance in both groups. Peak driving pressure and mean rate of rise of Pmus were greater in the KS. Increased intrinsic impedance, Pmus, and differences in changes in neural timing in anesthetized kyphoscoliotics contribute to modestly greater VT defense, compared to that of anesthetized subjects free of cardiorespiratory disease.
Carlson, M. E., Fanchiang, S. P., Zemke, R., & Clark, F. A. (1996). A meta-analysis of the effectiveness of occupational therapy for older persons. American Journal of Occupational Therapy, 50, 89-98. http://dx.doi.org/10.5014/ajot.50.2.89. Link to full text Abstract →
Given the current health care debate, it is imperative to document the usefulness of various health services for older persons, a rapidly growing population at increased risk for a wide variety of physical and functional impairments. A meta-analysis was conducted to examine the degree of effectiveness of occupational therapy for older persons. For a sample of 15 distinct tests of occupational therapy, a positive unweighted mean effect size of .51 (54 when corrected for instrument unreliability) was obtained, along with a highly significant cumulative result for treatment success (p < .001). Beneficial treatment effects extended to activities of daily living—functional and psychosocial outcomes. The results for physical outcomes suggested a beneficial effect, although not every meta-analytic test yielded significant results. It was concluded that factors such as publication bias or poor study design are incapable of accounting for the positive meta-analytic result and that occupational therapy represents a worthwhile treatment option for older persons.
Baydur, A. N., Sassoon, C. S., & Carlson, M. E. (1996). Measurement of lung mechanics at different lung volumes and esophageal levels in normal subjects: Effect of posture change. Lung, 174, 139-151. http://dx.doi.org/10.1007/BF00173306. Link to full text Abstract →
Lung elastance and resistance increase in the supine posture. To evaluate the effects of change in posture on regional lung mechanics at different lung volumes, lung elastance and resistance were measured at graded volume subdivisions and three esophageal levels at seated and supine body positions, using the esophageal balloon technique. Volumes were adjusted to be the same in both postures. In general, lung elastance (both static and dynamic) tended to be higher in supine posture and uniform at all lung volumes, except at 80% vital capacity, where it increased sharply. The ratio of dynamic to static lung elastance was slightly higher at the cephalad esophageal level, where regional flow rates and relative volume expansion are lower. Lung resistance varied inversely with lung volume but was higher at corresponding volume subdivisions in the supine posture. It decreased at more cephalad esophageal levels, where volume expansion and flow are less. Thus, the increase in regional flow at low volume subdivisions (most marked in the supine position) also contributed to higher lung resistance at these volumes. These findings are explained on the basis of a combination of Newtonian physics as well as nonlinear viscoelastic properties of the lung as applied to regional flow and volume expansion.
Carlson, M. E., Steindela, B. S., Roea, T. R., Costina, G., & Kaufman, F. (1995). Continuous subcutaneous insulin infusion (CSII) in children and adolescents with chronic poorly controlled type 1 diabetes mellitus. Diabetes Research and Clinical Practice, 27, 199-204. http://dx.doi.org/10.1016/0168-8227(95)01044-E. Link to full text Abstract →
This study was undertaken to determine if continuous subcutaneous insulin infusion (CSII) could improve control, diminish episodes of diabetic ketoacidosis (DKA), decrease number of hospitalizations and save health care expenditure in children and adolescents with long-standing poorly controlled diabetes mellitus. A retrospective analysis wasdone of six patients with type 1 diabetes for 1–8 years, of whom 4 were non-adherent to the diabetic regimen (ages 12–16.5 years) and 2 of whom had brittle diabetes (ages 8.5 and 10 years). These patients were non-randomly placed on the MiniMed (Sylmar, CA) CSII system. The year prior to CSII was compared with the year during pump use. Glycoslyated hemoglobin (HbA1c), spot urinary microalbumin, total cholesterol, insulin dose, growth velocity, number of convulsions and hypoglycemic events, number of episodes of DKA, number of hospitalizations and total inpatient costs were compared for the 2 years. The year prior to CSII, mean HbA1c was 9.02% (S.D. = 0.86%), mean number of hospitalizations was 5.2/patient (S.D. = 4.6), mean number of hospital days was 20.8/patient (S.D. = 14.7) and mean cost was $29330/patient (S.D. = $22804). During 1 year of CSII, mean number of hospital days decreased to 5 days/patient (S.D. = 0.8, P = 0.016), mean number of hospitalizations (including DKA and pump initiation) decreased to 1.7/patient (S.D. = 0.7, P = 0.31), mean inpatient costs decreased to $12762/patient (S.D. = $5.950, P = 0.047). HbA1c, urinary microalbumin, cholesterol, insulin dose and growth velocity did not change in a statistically significant manner. There were no significant adverse effects. It is concluded that CSII can be used safely in young patients with poorly controlled diabetes to diminish DKA, reduce number of hospitalizations and reduce health care costs.
Carlson, M. E., & Dunlea, A. (1995). Further thoughts concerning the pitfalls of partition: A response to Mosey. American Journal of Occupational Therapy, 49, 73-81. http://dx.doi.org/10.5014/ajot.49.1.73. Link to full text Abstract →
In her recent article, "Partition of Occupational Science and Occupational Therapy: Sorting Out Some Issues," Mosey (1993) responded to a rebuttal (Clark et al.. 1993) to her previous position paper (Mosey, 1992a) in which she had advocated the complete separation (i,e., partition) of occupational therapy and occupational science. In her 1993 article, Mosey reiterated her original theses that: (a) occupational therapy has an already sufficient existing fund of relevant theoretical knowledge to support its practice; (b) professions (including occupational therapy) do not and should not undertake basic research; and (c) the Iabor and financial resources of occupational therapy that are targeted for research should be devoted solely to applied inquiry and not basic inquiry, including occupational science. The present article is a rejoinder to Mosey's latest contentions. The format of our presentation corresponds to the five general topical headings employed by Mosey (1993); under each heading we summarize and then address her main points. However, before dealing with Mosey's specific concerns, we provide a definition of basic research to set the context for the remainder of our response.
Baydur, A. N., & Carlson, M. E. (1994). Respiratory mechanics by the passive relaxation technique in conscious healthy adults and patients with restrictive respiratory disorders. Chest, 105, 1171-1178. http://dx.doi.org/10.1378/chest.105.4.1171. Link to full text Abstract →
The passive relaxation single-breath technique has been used primarily in anesthetized human subjects to measure total respiratory system elastance and resistance. This method was used to assess the pressure-flow characteristics in 32 relaxed, conscious patients with restrictive respiratory disorders (20 with neuromuscular disease, 12 with sarcoidosis) and 27 similarly aged control subjects free of cardiothoracic disease. Using Robrer's pressure-flow relationship during passive expiration, P/V=K1+K2V, considerable curvilinear pressure-flow characteristics were found in both groups. These can be attributed to a combination of the upper airway and viscoelastic and elastoplastic behavior of the respiratory system
Baydur, A. N., Pandya, K., Sharma, O. P., Kanel, G. C., & Carlson, M. E. (1993). Control of ventilation, respiratory muscle strength, and granulomatous involvement of skeletal muscle in patients with sarcoidosis. Chest, 103, 396-402. http://dx.doi.org/10.1378/chest.103.2.396. Link to full text Abstract →
Granulomatous involvement of skeletal muscle occurs in 50 to 80 percent of patients with sarcoidosis. How this may affect respiratory muscle function in sarcoidosis is not known. To attempt to answer this question, we compared respiratory function and muscle force generation, and control of ventilation in 12 untreated patients with 12 healthy, nonsmoking subjects. While seated, room air breathing, measurements included expiratory reserve volume (ERV), components of breathing pattern, and occlusion pressure at 1 s (P0.1). Three of nine patients who consented to muscle biopsy demonstrated granulomatous involvement on histologic examination, and Pmax values less than the group mean; however, some patients without muscle granulomas also demonstrated low Pmax values. Breathing pattern in the sarcoid patients was rapid and shallow, but not related to the degree of radiographic infiltration or respiratory elastance. Mean inspiratory flow (VT/TI), minute ventilation, and P0.1 were, in general, greater than in the control subjects, indicating an increase in central drive. There was a significant inverse correlation between FVC and P0.1, and a weak inverse relationship between ERV and P0.1. With no significant difference between group "effective impedances" (P0.1/(VT/TI)), findings indicate that in the sarcoidosis group, decreased muscle force generation was compensated for by an increase in central drive. Granulomatous infiltration may be one of many factors contributing to respiratory muscle weakness in sarcoidosis.
Clark, F. A., Zemke, R., Frank, G., Parham, D., Neville-Jan, A. M., Hedricks, C., Carlson, M. E., Fazio, L., & Abreu, B. (1993). Dangers inherent in the partition of occupational therapy and occupational science [The issue is]. American Journal of Occupational Therapy, 47, 184-186. http://dx.doi.org/10.5014/ajot.47.2.184. Link to full text
Devereaux, E., & Carlson, M. E. (1992). The role of occupational therapy in the management of depression [Health policy]. American Journal of Occupational Therapy, 46, 175-180. http://dx.doi.org/10.5014/ajot.46.2.174. Link to full text Abstract →
This document was prepared at the request of the Depression Panel of the Office of the Forum for Quality and Effectiveness in Health Care within the Agency for Health Care Policy and Research, an agency of the U.S. Public Health Service. The panel was charged to develop clinical practice guidelines for the management of depression to be used by general medical and family medicine practitioners in primary care settings. The form of the panel's questions shaped the introductory portion of the document. After receiving the questions posed by the panel (which are stated later in this document), it was necessary to define the context of the use of occupation and occupational therapy to broaden the panel's understanding of these terms.
Clark, F. A., Parham, D., Carlson, M. E., Frank, G., Jackson, J. M., Pierce, D., Wolf, R. J., & Zemke, R. (1991). Occupational science: Academic innovation in the service of occupational therapy's future. American Journal of Occupational Therapy, 45, 300-310. http://dx.doi.org/10.5014/ajot.45.4.300. Link to full text Abstract →
Occupational science is a new scientific discipline that is defined as the systematic study of the human as an occupational being. A doctoral program in occupational science has been established at the University of Southern California, Los Angeles. With its emphasis on the provision of a multidimensional description of the substrates, form, function, meaning, and sociocultural and historical contexts of occupation, occupational science emphasizes the ability of humans throughout the life span to actively pursue and orchestrate occupations. In this paper, occupational science is described, defined, and distinguished from other social sciences. A general systems model is presented as a heuristic to explain occupation and organize knowledge in occupational science. The development of occupational science offers several key benefits to the profession of occupational therapy, including (a) fulfillment of the demand for doctoral-level faculty members in colleges and universities; (b) the generation of needed basic science research; and (c) the justification for and potential enhancement of practice.
Carlson, M. E., & Clark, F. A. (1991). The search for useful methodologies in occupational science. American Journal of Occupational Therapy, 45, 235-242. http://dx.doi.org/10.5014/ajot.45.3.235. Link to full text Abstract →
Debate currently exists on the soundness of various research methodologies in the social sciences. In the present paper, this question is addressed in relation to the emerging discipline of occupational science. First, the discipline of occupational science is defined. Next, two competing methodologies—Paradigm 1, Positivistic, and Paradigm 2, Naturalistic—are contrasted. The criteria of genuineness and trustworthiness are proposed as crucial for the evaluation of the soundness of available research methodologies for the extension of occupational science. Next, exemplars of research methodologies that meet these criteria are described. In the conclusion, the role that nonscientific ways of knowing, such as art and literature, may play in the understanding of human occupation is discussed.
Roe, T. F., Mora, S., Costin, G., Kaufman, F., Carlson, M. E., & Gilsanz, V. (1991). Vertebral bone density in insulin-dependent diabetic children. Metabolism: Clinical and Experimental, 40, 967-971. http://dx.doi.org/10.1016/0026-0495(91)90074-7. Link to full text Abstract →
To determine the effect of insulin-dependent diabetes mellitus (IDDM) on bone mass, we compared the trabecular and cortical bone density in lumbar vertebrae, measured by quantitative computed tomography (CT), in 48 white diabetic patients (23 females, 25 males; 5.2 to 19.6 years of age) with those of a control group of 48 healthy subjects, matched for race, sex, and age. Patients with neuropathy, retinopathy, nephropathy, and those with recent ketoacidosis were excluded from the study. The patient and control groups did not differ in sexual or skeletal maturation, weight, height, surface area, body mass index, abdominal fat, or paraspinal musculature. In diabetic children, cortical bone density was slightly but significantly lower than in controls (3.5% lower, P less than .02); there was no difference between patients and controls regarding trabecular bone density. The decrease in cortical bone density in the diabetic group did not correlate with age, sex, duration of diabetes, or glycosylated hemoglobin levels. These results suggest that in children with uncomplicated IDDM, decreased vertebral bone density is a minor abnormality that only affects cortical bone.
Miller, N., Lee, J., & Carlson, M. E. (1991). The validity of inferential judgments when used in theory-testing meta-analysis. Personality and Social Psychology Bulletin, 17, 335-343. http://dx.doi.org/10.1177/0146167291173014. Link to full text Abstract →
Examines the use of inferential judgments in meta-analysis as a means of testing hypotheses in social psychological theory. A validity study based on 87 published articles is presented, which shows that judgments regarding the level of psychological mediators, as inferred from a reading of method sections of social psychological experiments, correlate highly with manipulation-check effect sizes. This was true for each of 2 affective mediators (positive and negative mood) and each of 2 cognitive mediators (perception of control and source credibility). However, judgments about Ss' helping behavior or attitude change were not so consistently related to dependent-measure effect sizes.
Gilsanz, V., Roe, T. F., Antunes, J., Carlson, M. E., Duarte, M. L., & Goodman, W. G. (1991). Effect of dietary calcium on bone density in growing rabbits. American Journal of Physiology, 260, E471-E476. Link to full text Abstract →
Reductions in peak bone mass at skeletal maturity may increase the risk for the subsequent development of osteoporosis. Although changes in calcium intake can modify the rate of decline in bone density in the mature skeleton, longitudinal assessments of the effect of dietary calcium supplementation during skeletal growth on peak bone mass have not been done in humans or experimental animals. Thus quantitative computed tomography (QCT) was used to monitor changes in vertebral bone density at 6-wk intervals during growth from 8 wk of age until skeletal maturity at 35 wk in male New Zealand White rabbits maintained on diets containing 0.15% (low Ca), 0.45% (normal Ca), or 1.35% (high Ca) calcium. Serum parathyroid hormone (PTH) and calcitriol levels increased, and renal calcium excretion decreased in low Ca compared with normal Ca; in contrast, serum calcitriol levels decreased and renal calcium excretion increased from control values in high Ca. Vertebral bone density by QCT did not differ during growth between high Ca and normal Ca, and peak values at epiphyseal closure also did not differ in these two groups. Vertebral bone density was lower, however, throughout the study in low Ca, and peak values at epiphyseal closure remained below those in either normal Ca or high Ca. Quantitative bone histology revealed decreases in cortical thickness in the third lumbar vertebra in low Ca, whereas trabecular bone area did not differ among groups; there was no histological evidence of osteomalacia in low Ca. Thus dietary calcium restriction during growth reduces peak bone mass at skeletal maturity, but raising dietary calcium intake above normal levels does not increase peak bone mass in this experimental model.
The relationship between long-term blood glucose control and albuminuria in type 1 diabetes was investigated in 42 male and 58 female patients who had had diabetes mellitus for more than 7 years. Their mean (±SD) age and diabetes duration were 18.6±3.6 and 12.1±3.5 years, respectively. For periods of observation ranging from 1 to 6 years (mean 4.4±1.5), hemoglobin A1c (HbA1c) was measured two to six times yearly (mean of 8.8±3.9 determinations per patient). Albumin excretion rate (AER) was measured in single-void urine samples two to four times in 93 patients and once in the other seven patients. The 52 patients with mean HbA1c no more than 9.0% had significantly lower mean AER than those whose HbA1c was greater than 9.0% (20.1±24.6 vs 265±1005 mg/gm Cr, p<0.001). Only five (9.6%) of these 52 patients had elevated AER values (>40 mg/gm Cr), whereas 21 (43.7%) of 48 patients whose mean HbA1c was greater than 9.0% had elevated AER values (p<0.001). Six male but no female patients had mean AER values greater than 300 mg/gm Cr. The 74 patients with normal AER had significantly lower mean HbA1c values than the 26 with elevated AER (8.6±1.5 vs 10.1±1.6%, p<0.001). These results support the contention that maintenance of HbA1c levels at no more than 9% (one and one-half times the upper limit of normal) will significantly decrease the likelihood that diabetic nephropathy will develop.
Gilsanz, V., Carlson, M. E., Roe, T. F., & Ortega, J. A. (1990). Osteoporosis after cranial irradiation for acute lymphoblastic leukemia. The Journal of Pediatrics, 117, 238-244. Link to full text Abstract →
A prospective study was conducted to investigate the possibility of osteoporosis after treatment for childhood acute lymphoblastic leukemia (ALL). Forty-two survivors of ALL had the trabecular bone density of the spine evaluated by quantitative computed tomography, 6 to 98 months (mean 42 months) after completion of chemotherapy. The ALL survivors had significantly lower bone density than age-, gender-, and race-matched nonleukemic control subjects had (10% less, p less than 0.001); this decrease was accounted for solely by the subset of patients who had received cranial irradiation (n = 30; p less than 0.001). The relative reduction in bone density in ALL survivors was unrelated to age at the time of diagnosis or time without therapy. The effects on bone density of 18 Gy and of 22.5 to 25.2 Gy were indistinguishable. We conclude that survivors of ALL commonly have reduced bone density in the lumbar spine and suggest that the diminution is related to nervous system irradiation, not to the disease or to chemotherapy.
Baydur, A. N., Gilgoff, I., Prentice, W., Carlson, M. E., & Fischer, D. A. (1990). Decline in respiratory function and experience with long-term assisted ventilation in advanced Duchenne's muscular dystrophy. Chest, 97, 884-889. http://dx.doi.org/10.1378/chest.97.4.884. Link to full text Abstract →
We present 17 patients with advanced DMD who required long-term assisted ventilation. Eleven patients used part-time assisted ventilation. Five of the patients received BV and/or M-IPPV or N-IPPV between two and nine years before requiring full-time T-IPPV, while six others initially used part-time T-IPPV. One patient used all three modes before requiring full-time T-IPPV. Mean (+/- SD) FVC and rebreathe PCO2 at the outset of assisted ventilation were 0.62 +/- 0.20 L and 47.4 +/- 7.5 mm Hg, respectively. Clinical features were divided between symptoms suggesting respiratory muscle fatigue and sleep-related disordered breathing. We found that, while useful in early respiratory insufficiency, BV is associated with recurrent aspiration. In our experience, N-IPPV offers the safest and most convenient form of noninvasive ventilation. When the VC has decreased to about 300 ml, most patients will require full-time ventilation; T-IPPV is advised to provide airway access to suction secretions.
Carlson, M. E., Marcus-Newhall, A., & Miller, N. (1990). Effects of situational aggression cues: A quantitative review. Journal of Personality and Social Psychology, 58, 622-633. http://dx.doi.org/10.1037/0022-35184.108.40.2062. Link to full text Abstract →
Meta-analytic procedures were used to assess the degree to which aggression-related cues present in the environment facilitate aggressive responding among negatively aroused subjects. The first study, which examined the so-called weapons effect, the effect of name-mediated cues, and other cue effects, showed clear evidence that aggression cues augment aggressive responses in negatively aroused subjects. This was true for the overall analysis and for name-mediated cues, but confirmation of the weapons effect was restricted to cases wherein subject sophistication and evaluation apprehension were low. A second study used partial correlation analysis to assess independently the effects of seven potential mediators of aggression cue effects. Of these, target-based facilitation and harm capacity of the aggressive response were found to mediate the magnitude of cue-facilitated aggression. A third study showed that these mediators augmented cue effects among neutral as well as negatively aroused subjects. These outcomes are interpreted as emphasizing the role of cognitive factors in the expression of both impulsive and nonimpulsive aggression.
Miller, N., & Carlson, M. E. (1990). Valid theory testing meta-analyses further question the Negative State Relief model of helping. Psychological Bulletin, 107, 215-225. http://dx.doi.org/10.1037/0033-2909.107.2.215. Link to full text Abstract →
R. B. Cialdini and J. Fultz (see record 1990-14623-001) questioned the validity of M. Carlson and N. Miller's (see record 1987-31249-001) method and objected to 3 reported tests of their negative state relief (NSR) model of mood-induced increments to helpfulness. In response, evidence is presented that the use of judges to define variables is a common tool in psychology and, when used within meta-analyses, consistently meets the relevant criteria of convergent, discriminant trait, and construct validity. Multiple new tests based directly on the more objective criteria that Cialdini and Fultz stipulate for defining NSR variables fail to support their model. New data they presented to challenge the discriminant validity of judges' ratings are shown to be based on methodologically and conceptually flawed procedures. Finally, they reported a (nonsignificant) positive correlation between sadness-manipulation check effect sizes and helpfulness effect sizes, in support of the NSR model. When this correlation was computed in 9 different ways on the basis of more extensive sets of studies, it was uniformly close to zero and nonsignificant, thereby supporting Carlson and Miller's prior meta-analytic outcome.
The densities of the trabecular bone of two or three lumbar vertebral bodies in twenty adolescents, twelve to eighteen years old, who had Scheuermann disease were measured by quantitative computed tomography. These densities were then compared with those for the same vertebrae of twenty age, sex, and race-matched adolescents who were examined by computed tomography because of trauma. The same scanner and phantom were used in all examinations. Both the adolescents who had Scheuermann disease and the control patients were in good health before the quantitative computed-tomography examination and had not been taking any medications. The density of the trabecular bone density in the patients who had Scheuermann disease was not significantly different (p = 0.28) from that in the controls. There also were no significant differences between the patients and the controls with regard to height, weight, surface area, or body-mass index.
Gilsanz, V., Gibbens, D. T., Carlson, M. E., Boechat, M. I., & Tolo, V. T. (1989). The effect of limping on vertebral bone density: A study of children with tarsal coalition. Journal of Pediatric Orthopedics, 9, 33-36. Link to full text Abstract →
To determine whether limping is associated with decreased bone mineralization, the trabecular and integral bone densities (BDs) of 18 Caucasian children exhibiting computed tomographic evidence of tarsal coalition (14 boys, 4 girls, aged 9 years, 5 months to 16 years, 3 months) were compared with those of an age- and sex-matched control group. Patients with tarsal coalition had significantly lower trabecular (p less than 0.05) and integral (p less than 0.05) BD than controls. Trabecular spinal density was approximately 17% lower on the average in patients with tarsal coalition. Among the limping patients, neither the duration of symptoms nor bilaterality was associated with decreased BD. The findings suggest that painful tarsal coalition may decrease vertebral bone mass and predispose to spinal osteoporosis.
Carlson, M. E., Marcus-Newhall, A., & Miller, N. (1989). Evidence for a general construct of aggression. Personality and Social Psychology Bulletin, 15, 377-389. http://dx.doi.org/10.1177/0146167289153008. Link to full text Abstract →
Three analyses of published research were undertaken to assess whether diverse laboratory response measures that are intended to measure aggression reflect a common underlying construct. It was found that (a) alternative measures of physical aggression directed by the same subjects against the same target tend to intercorrelate positively within studies, (b) across studies, the correlations between effect-size estimates of physical and written aggression emitted by the same subjects are positive, and (c) physical and written aggressive responses are similarly influenced by theoretically relevant antecedent factors (e.g., personal attack and frustration). The consistent overall pattern of results supports the notion that aggression, defined as intent to harm, is a viable construct that possesses some degree of generality.
Gilsanz, V., Roe, T. F., Gibbens, D. T., Schulz, E. E., Carlson, M. E., Gonzalez, O., & Boechat, M. I. (1988). Effect of sex steroids on peak bone density of growing rabbits. American Journal of Physiology: Endocrinology and Metabolism, 255, E416-E421. Link to full text Abstract →
To determine the effect of sex hormones on bone density (BD) during growth, longitudinal quantitative computed tomography (QCT) measurements were obtained in growing, castrated New Zealand White rabbits following administration of normal saline, testosterone, or estrogen from 6 wk of age until the time of skeletal maturity. Vertebral QCT densities increased during growth, were highest at the time of epiphyseal closure, and were significantly greater (P less than 0.001) in hormone-treated animals. In vivo QCT measurements in 12 vertebraes correlated strongly (r = 0.92) with percentage of calcium per weight assessed in vitro by neutron activation analysis.
Gilsanz, V., Gibbens, D. T., Roe, T. F., Carlson, M. E., Senac, M. O., Boechat, M. I., Huang, H. K., Schulz, E. E., Libanati, C. R., & Cann, C. C. (1988). Vertebral bone density in children: Effect of puberty. Radiology, 166, 847-850. Link to full text Abstract →
To determine changes in bone density during growth, trabecular vertebral density and an index of spinal cortical bone were measured with quantitative computed tomography in 101 children. The children were divided by age into three groups: prepubertal, indeterminate, and pubertal. Compared with prepubertal children, pubertal adolescents had significantly higher trabecular bone density and more compact bone in the spine (P less than .001). After controlling for puberty, vertebral bone density failed to correlate significantly with age, sex, weight, height, surface area, and body mass index. The results indicate that bone density increases markedly during puberty.
To determine if osteoporosis is prevalent among patients with cystic fibrosis, we compared the vertebral bone density measured by quantitative computed tomography in 57 such patients (29 male, 28 female, aged 3 to 21 years) with those of an age-, race-, and sex-matched control group of 57 healthy subjects. Patients with cystic fibrosis had significantly lower bone density (10% lower, p less than 0.001) than in controls. The decrease in bone density in patients with cystic fibrosis was unrelated to age. Shwachman clinical evaluation scores (based on case history, pulmonary physical findings, growth, and x-ray findings) correlated positively with age-standardized bone density values (p less than 0.01). Male patients had substantially lower bone density than did female patients (p less than 0.02), but bone density differences related to gender were not significant when effects of disease severity were controlled for. Decreased bone density was more common in patients with poor nutritional status as determined by anthropometric measurements (p less than 0.05). We conclude that osteoporosis is a frequent complication in children with cystic fibrosis regardless of their age and is more prevalent in patients with greater disease severity.
Gilsanz, V., Gibbens, D. T., Carlson, M. E., Boechat, M. I., Cann, C. E., & Schulz, E. E. (1988). Peak trabecular vertebral density: A comparison of adolescent and adult females. Calcified Tissue International, 43, 260-262. http://dx.doi.org/10.1007/BF02555144. Link to full text Abstract →
To determine when spinal bone density reaches its peak, the trabecular vertebral density was assessed, via quantitative computed tomography, among females from two age groups: (1) adolescents (aged 14–19 years; n=24); and (2) young adults (aged 25–35 years; n=24). The adolescent girls had a higher mean trabecular vertebral density (P<0.01), suggesting that spinal density reaches its peak around the time of cessation of longitudinal growth and epiphyseal closure.
Carlson, M. E., & Miller, N. (1988). Bad experiences and aggression. Sociology and Social Research, 72, 155-188.
Carlson, M. E., & Miller, N. (1988). The differential effects of social and nonsocial negative events on aggressiveness. Sociology and Social Research, 72(3), 155-158.
Carlson, M. E., Charlin, V., & Miller, N. (1988). Positive mood and helping behavior: A test of six hypotheses. Journal of Personality and Social Psychology, 55, 211-229. http://dx.doi.org/10.1037/0022-35220.127.116.11. Link to full text Abstract →
Past research has shown rather consistently that positive mood states lead to increased helpfulness. In an expanded analysis of the published literature, we examined six distinct views about this relation: the focus of attention, objective self-awareness, separate process, social outlook, mood maintenance, and concomitance hypotheses. For each of 61 positive affect conditions in which it was possible to generate an effect-size estimate corresponding to the relative degree of helpfulness exhibited by positive mood subjects (compared with neutral affect subjects), judges assessed the contextual levels of variables relevant to each of the six hypotheses by reading the Method section of each article. Higher-order partial correlation coefficients were then calculated to isolate the independent contribution of each of the theoretically relevant variables to the variation among the 61 effect sizes. The results support the focus of attention, separate process, social outlook, and mood maintenance hypotheses, and partially support the objective self-awareness and concomitance hypotheses.
King, J., Diefendorf, D., Apthorp, J., Negrete, V. F., & Carlson, M. E. (1988). Analysis of 429 fractures in 189 battered children. Journal of Pediatric Orthopedics, 8, 585-589. Link to full text Abstract →
To assess empirically the radiologic appearance of fractures among victims of child abuse, the charts and radiographs of 189 battered children exhibiting fractures (n = 429 total fractures) were studied. Approximately one-half of the patients had a single fracture. Bones most commonly fractured were the humerus, femur, and tibia; transverse fractures were the most common type. Of long bone fractures, the middle third (50%) and distal third (41%) locations were most prominent. Age, race, and gender were not associated with any particular long bone fracture type. Skull fractures were the only type more likely to be present in children aged less than 1 year than in older children (p less than 0.05, one-tailed). In the past, emphasis has been placed on corner fractures, fractures at different stages of healing, and injuries at several sites. Our results suggest that fresh single diaphyseal fractures are more common.
Carlson, M. E., & Miller, N. (1987). Explanation of the relation between negative mood and helping. Psychological Bulletin, 102(1), 91-108. Abstract →
Prior research addressing the relation between negative affect and helping behavior has yielded inconsistent results. Three theoretical interpretations, negative-state relief, attentional focus, and responsibility/objective self-awareness, are examined in an expanded analysis of published research. For this purpose, judges assessed for each of 85 negative affect conditions the contextual levels of the variables relevant to each theory by reading relevant material that was excerpted from the method section of each article. Higher order partial correlations were then calculated between each variable and the 85 helpfulness effect sizes. The results are consistent with the attentional focus and the responsibility/objective self-awareness models. Both increased perceptions of responsibility for causing the negative event and attentional focus on another (as opposed to oneself) as the target of the negative event augment helpfulness. Furthermore, mood-lowering events that engender objective self-awareness promote helpfulness when prosocial values are psychologically salient. No support obtains for the negative-state relief model.
Carlson, M. E. (1987). Abnormal bone density following treatment for childhood acute lymphoblastic leukemia. Osteoporosis, 2, 1085-1087.
Gilsanz, V., Schulz, E. E., Gibbens, D. T., Roe, T. F., Boechat, M. I., Carlson, M. E., & Cann, C. E. (1987). Puberty, sex steroids and bone density. Osteoporosis, 435-437.
Thomas, D. W., McGilligan, K. M., Carlson, M. E., Azen, S. P., Eisenberg, L. D., Lieberman, H. M., & Rissman, E. M. (1986). Fecal alpha-1-antitrypsin and hemoglobin excretion in healthy human milk-, formula-, or cow’s milk-fed infants. Pediatrics, 78, 305-312. Link to full text Abstract →
There is concern that whole cow's milk feedings may be associated with intestinal abnormalities in infants. We studied this issue by measuring random fecal samples for 1-antitrypsin (FA1AT) and hemoglobin (FH) concentrations in 820 healthy infants up to 12 months of age. Subjects were fed either human milk, formula, or fresh whole cow's milk. Solid foods were given ad libitum. Fecal samples were also tested for occult blood with Hematest reagent tablets. None of the infants younger than 6 months of age were receiving fresh whole cow's milk. We found small but statistically significant differences in mean FA1AT between the three feeding groups (P < .0001): human milk (n = 354) > formula (n = 320) > cow's milk (n = 146). The younger subjects fed either formula or human milk tended to have higher FA1AT concentrations than did the age-matched subjects who were not consuming solid foods (P .005). Daily FA1AT excretion, FA1AT concentration, and daily stool output were subsequently determined on a separate group of 40 infants 8 to 12 months of age to ascertain whether differences in total daily FA1AT excretion occur in children fed different types of milk. Total daily FA1AT excretion was similar in the three milk feeding groups. An inverse correlation between FA1AT concentration and daily stool output was also found (P < .001). The overall rate of detectable FH in 792 stool smears was 2.1% and unrelated to type of milk feeding. Of 705 stool smears, 3.5% had positive Hematest reactions. Our results indicate that exudative protein loss or intestinal bleeding, as determined by FA1AT and FH, are uncommon in healthy cow's milk-fed infants older than 6 months of age. Dietary intake of solid foods and type of milk feeding should be considered when analyzing random stool samples for FA1AT concentration in young infants. Normal human milk-fed infants may have "high" FA1AT content because of reduced stool output.
Clark, F. A., Carlson, M. E., Jackson, J. M., & Mandel, D. (2003). Lifestyle Redesign: Improves health and is cost-effective. OT Practice, 8(2), 9-13. Link to full text