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1.  Diurnal patterns and associations among salivary cortisol, DHEA and alpha-amylase in older adults☆ 
Physiology & behavior  2014;129:11-16.
Cortisol and dehydroepiandrosterone (DHEA) are considered to be valuable markers of the hypothalamus–pituitary–adrenal (HPA) axis, while salivary alpha-amylase (sAA) reflects the autonomic nervous system. Past studies have found certain diurnal patterns among these biomarkers, with some studies reporting results that differ from others. Also, some past studies have found an association among these three biomarkers while other studies have not. This study investigates these patterns and associations in older adults by taking advantage of modern statistical methods for dealing with non-normality, outliers and curvature. Basic characteristics of the data are reported as well, which are relevant to understanding the nature of any patterns and associations.
Boxplots were used to check on the skewness and presence of outliers, including the impact of using simple transformations for dealing with non-normality. Diurnal patterns were investigated using recent advances aimed at comparing medians. When studying associations, the initial step was to check for curvature using a non-parametric regression estimator. Based on the resulting fit, a robust regression estimator was used that is designed to deal with skewed distributions and outliers.
Boxplots indicated highly skewed distributions with outliers. Simple transformations (such as taking logs) did not deal with this issue in an effective manner. Consequently, diurnal patterns were investigated using medians and found to be consistent with some previous studies but not others. A positive association between awakening cortisol levels and DHEA was found when DHEA is relatively low; otherwise no association was found. The nature of the association between cortisol and DHEA was found to change during the course of the day. Upon awakening, cortisol was found to have no association with sAA when DHEA levels are relatively low, but otherwise there is a negative association. DHEA was found to have a positive association with sAA upon awakening. Shortly after awakening and for the remainder of the day, no association was found between DHEA and sAA ignoring cortisol. For DHEA and cortisol (taken as the independent variables) versus sAA (the dependent variable), again an association is found only upon awakening.
PMCID: PMC4041594  PMID: 24568897
Cortisol; Dehydroepiandrosterone (DHEA); Salivary alpha-amylase; Well Elderly II study
2.  Implementing trials of complex interventions in community settings: The USC – Rancho Los Amigos Pressure Ulcer Prevention Study (PUPS) 
Clinical trials (London, England)  2014;11(2):218-229.
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: (a) participant recruitment and retention, (b) intervention delivery and fidelity, (c) randomization and assessment, and (d) potential inadvertent treatment effects.
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.
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.
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 accord with a rigorous plan. Finally, we have overcome unanticipated assessment and design concerns related to: (a) determining pressure ulcer incidence/severity, (b) randomization imbalance, and (c) inadvertent potential control group contamination.
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.
Overcoming challenges has required a multifaceted approach incorporating individualization, flexibility, and persistence as well as the ability to implement needed mid-course corrections.
PMCID: PMC3972348  PMID: 24577972
Spinal cord injury; pressure ulcer prevention; RCTs of multicomponent individualized interventions; underserved minority research participants
3.  Cortisol Diurnal Patterns, Associations with Depressive Symptoms, and the Impact of Intervention in Older Adults: Results Using Modern Robust Methods Aimed at Dealing with Low Power Due to Violations of Standard Assumptions 
Hormones and behavior  2014;65(3):219-225.
Advances in salivary bioscience enable the widespread integration of biological measures into the behavioral and social sciences. While theoretical integration has progressed, much less attention has focused on analytical strategies and tactics. The statistical literature warns that common methods for comparing groups and studying associations can have relatively poor power compared to more modern robust techniques. Here we illustrate, in secondary data analyses using the USC Well Elderly II Study (n = 460, age 60-95, 66% female), that modern robust methods make a substantial difference when analyzing relations between salivary analyte and behavioral data. Analyses are reported that deal with the diurnal pattern of cortisol and the association of the cortisol awakening response with depressive symptoms and physical well-being. Non-significant results become significant when using improved methods for dealing with skewed distributions and outliers. Analytical strategies and tactics that employ modern robust methods have the potential to reduce the probability of both Type I and Type II errors in studies that compare salivary analytes between groups, across time, or examine associations with salivary analyte levels.
PMCID: PMC3960304  PMID: 24468639
robust statistical techniques; cortisol awakening response; depressive symptoms; well-being; Well Elderly II study
4.  Lifestyle Changes and Pressure Ulcer Prevention in Adults With Spinal Cord Injury in the Pressure Ulcer Prevention Study Lifestyle Intervention 
The American Journal of Occupational Therapy  2014;69(1):6901290020p1-6901290020p10.
Examination of the interaction between lifestyle choices and the development of pressure ulcers revealed four patterns relating PrU development to lifestyle changes.
Pressure ulcers (PrUs) are a major burden to patients with spinal cord injury (SCI), affecting their psychological, physical, and social well-being. Lifestyle choices are thought to contribute to the risk of developing PrUs. This article focuses on the interaction between lifestyle choices and the development of PrUs in community settings among participants in the University of Southern California–Rancho Los Amigos National Rehabilitation Center Pressure Ulcer Prevention Study (PUPS II), a randomized controlled trial of a lifestyle intervention for adults with SCI. We conducted a secondary cross-case analysis of treatment notes of 47 PUPS II participants and identified four patterns relating PrU development to lifestyle changes: positive PrU changes (e.g., healing PrUs) with positive lifestyle changes, negative or no PrU changes with positive lifestyle changes, positive PrU changes with minor lifestyle changes, and negative or no PrU changes with no lifestyle changes. We present case studies exemplifying each pattern.
PMCID: PMC4281707  PMID: 25553751
life style; pressure ulcer; risk reduction behavior; spinal cord injuries; tertiary prevention
5.  Conducting Intervention Research among Underserved Populations: Lessons Learned and Recommendations for Researchers 
Randomized controlled trials (RCTs) are considered the gold standard in research design for establishing treatment efficacy. However, the rigorous and highly controlled conditions of RCTs can be difficult to attain when conducting research among individuals living with a confluence of disability, low socioeconomic status, and being a member of a racial/ethnic minority group, who may be more likely to have unstable life circumstances. Research on effective interventions for these groups is urgently needed, as evidence regarding approaches to reduce health disparities and improve health outcomes is lacking. In this methodological paper we discuss the challenges and lessons learned in implementing the Lifestyle Redesign® for Pressure Ulcer Prevention in Spinal Cord Injury (LR-PUPS) study among a highly disadvantaged population. These issues are discussed in terms of strategies to enhance recruitment, retention, and intervention relevance to the target population. Recommendations for researchers seeking to conduct RCTs among socioeconomically disadvantaged, ethnically diverse populations are provided.
PMCID: PMC3669234  PMID: 23262157
Spinal Cord Injuries; Pressure Ulcer; Life Style; Vulnerable Populations
6.  Dissemination: Bringing Translational Research to Completion 
Despite the availability of innovative health care research, a gap exists between research-generated knowledge and the utilization of that knowledge in real-world practice settings. This article examines the transition from research to implementation in the context of the dissemination of A. Jean Ayres’ sensory integration procedures and of the challenges currently facing the University of Southern California Well Elderly Studies research team. Drawing from the emerging field of implementation science, this article discusses how researchers can develop an implementation plan to more easily translate evidence into practice. Such plans should address the intervention’s reach (i.e., its capacity to penetrate into the intended target population), the settings for which it is applicable, the leaders who will encourage practitioner uptake, stakeholder groups, and challenges to dissemination. By taking action to ensure the more effective dissemination of research-generated knowledge, researchers can increase the likelihood that their interventions will lead to improvements in practice and more effective care for consumers.
PMCID: PMC3722656  PMID: 23433273
diffusion of innovation; evidence-based practice; information dissemination; translational medical research
Human factors  2011;53(5):431-447.
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 in order to investigate the relationship computer use has with demographics, well-being and other key psychosocial variables in older adults.
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 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.
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: email and general computer use.
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.
Study findings highlight differences in computer usage, especially in regard to Hispanic ethnicity and specific health and well-being factors.
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.
PMCID: PMC3211095  PMID: 22046718
8.  Individualization of a Manualized Pressure Ulcer Prevention Program: Targeting Risky Life Circumstances Through a Community-Based Intervention for People with Spinal Cord Injury 
Advances in skin & wound care  2011;24(6):275-286.
To sensitize practitioners working with individuals with spinal cord injury to the complex life circumstances that are implicated in the development of pressure ulcers, and to document the ways that interventions can be adapted to target individual needs.
Content analysis of weekly fidelity/ quality control meetings that were undertaken as part of a lifestyle intervention for pressure ulcer prevention in community-dwelling adults with spinal cord injury.
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.
Attention to recurrent types of individual needs, along with explicit strategies for tailoring manualized interventions, has potential to enhance pressure ulcer prevention efforts for adults with spinal cord injury.
Target audience
This continuing education article is intended for practitioners interested in learning about a comprehensive, context-sensitive, community-based pressure ulcer prevention program for people with spinal cord injury.
After reading this article, the reader should be able to: Describe some of the contextual factors that increase pressure ulcer risk in people with spinal cord injury living in the community.Distinguish between tailored and individualized intervention approaches.Identify the issues that must be taken into account to design context-sensitive, community-based pressure ulcer prevention programs for people with spinal cord injury.Describe approaches that can be used to individualize manualized interventions.
PMCID: PMC3374501  PMID: 21586911
9.  Psychometric Properties of Reverse-Scored Items on the CES-D in a Sample of Ethnically Diverse Older Adults 
Psychological assessment  2011;23(2):558-562.
Reverse-scored items on assessment scales increase cognitive processing demands, and may therefore lead to measurement problems for older adult respondents.
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 non-reversed items, (b) disproportionately lead to intra-individually 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 non-reversed CES-D items, the four reversed items were less internally consistent, were associated with lower item-scale correlations, and were more often answered atypically at an intra-individual level. Further, the atypical responses were negatively correlated with responses to psychometrically sound non-reversed 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 re-administration or statistical imputation be applied to reduce the difficulties.
PMCID: PMC3115428  PMID: 21319906
CES-D; depression; reversed item format; older adults
10.  Manualization of Occupational Therapy Interventions: Illustrations from the Pressure Ulcer Prevention Research Program 
The manualization of a complex occupational therapy intervention is a crucial step in ensuring treatment fidelity for both clinical application and research purposes. Towards this latter end, intervention manuals are essential for assuring trustworthiness and replicability of randomized controlled trials (RCT’s) that aim to provide evidence of the effectiveness of occupational therapy. In this paper, literature on the process of intervention manualization is reviewed. The prescribed steps are then illustrated through our experience in implementing the University of Southern California/Rancho Los Amigos National Rehabilitation Center’s collaborative Pressure Ulcer Prevention Project (PUPP). In this research program, qualitative research provided the initial foundation for manualization of a multifaceted occupational therapy intervention designed to reduce incidence of medically serious pressure ulcers in people with SCI.
PMCID: PMC3254151  PMID: 22214116
Translational Science; Clinical Trials; Treatment Fidelity
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.
PMCID: PMC3177298  PMID: 20649161
12.  Factor Structure, Reliability and Convergent Validity of the Engagement in Meaningful Activities Survey for Older Adults 
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, persons 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.
PMCID: PMC3172818  PMID: 21927592
Measurement; Meaning and Purpose in Life; Health-Related Qualify of Life; Life Satisfaction
13.  Effectiveness of a lifestyle intervention in promoting the well-being of independently living older people: results of the Well Elderly 2 Randomised Controlled Trial 
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.
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.
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.
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.
Trial Registration identifier: NCT0078634.
PMCID: PMC3412049  PMID: 21636614
Lifestyle interventions; occupational therapy; randomised controlled trial; quality of life; ageing/geriatrics; depression; geriatrics; lifestyle; qual of life measmnt; randomised trials
14.  Decisions and Dilemmas in Everyday Life: Daily Use of Wheelchairs by Individuals with Spinal Cord Injury and the Impact on Pressure Ulcer Risk 
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.
PMCID: PMC3098129  PMID: 21603085
daily routines; paraplegia; pressure ulcers; spinal cord injury; tetraplegia; wheelchair; wheelchair cushion
15.  Confronting Challenges in Intervention Research with Ethnically Diverse Older Adults: The USC Well Elderly II Trial 
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.
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.
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 six 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.
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.
Methodological challenges were encountered in the areas of site recruitment, participant recruitment, testing, and intervention delivery.
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.
PMCID: PMC3073495  PMID: 19254939
Older adults; randomized clinical trials; lifestyle intervention; health-related quality of life; methodological challenges; recruitment strategies

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