Edward H Ip

Wake Forest School of Medicine, Winston-Salem, NC, USA

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Publications (34)129.64 Total impact

  • Article: The MAT-sf: Clinical Relevance and Validity.
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    ABSTRACT: BACKGROUND: The measurement of mobility is essential to both aging research and clinical practice. A newly developed self-report measure of mobility, the mobility assessment tool-short form (MAT-sf), uses video animations to improve measurement accuracy/precision. Using a large baseline data set, we recalibrated the items, evaluated the extent to which older patients' self-efficacy (i.e., confidence) for walking was related to MAT-sf scores beyond their actual 400-m walk time, and assessed the relationship of the MAT-sf with body mass index and other clinical variables. METHODS: The analyses employed baseline data from the Lifestyle Interventions and Independence for Elders Study. RESULTS: Item recalibration demonstrated that the MAT-sf scoring algorithm was robust. In an analysis with 400-m walk time and self-efficacy regressed on the MAT-sf, both variables shared unique variance with the MAT-sf (p < .001). The MAT-sf was inversely related to several comorbidities, most notably hypertension and arthritis (p < .001), and scores were lowest when body mass index ≥ 35kg/m(2). Finally, MAT-sf scores were directly related to Short Physical Performance Battery scores, inversely related to difficulty with activities of daily living (p < .001) and higher for men than for women (p < .001). CONCLUSIONS: The findings extend the validity and clinical utility of this innovative tool for assessing self-reported mobility in older adults. Longitudinal data on the MAT-sf from the Lifestyle Interventions and Independence for Elders Study will enable us to evaluate the relative contributions of self-report and performance-based measures of mobility on important health outcomes.
    The Journals of Gerontology Series A Biological Sciences and Medical Sciences 05/2013; · 4.60 Impact Factor
  • Article: Psychometric properties of a computerized adaptive test for assessing mobility in older adults using novel video-animation technology.
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    ABSTRACT: PURPOSE: This paper reports on the psychometric properties of a computerized adaptive test (CAT) version of the Mobility Assessment Tool (MAT) for older adults (MAT-CAT). METHODS: An item pool of 78 video-animation-based items for mobility was developed, and response data were collected from a sample of 234 participants aged 65-90 years. The video-animation-based instrument was designed to minimize ambiguity in the presentation of task demands. In addition to evaluating traditional psychometric properties including dimensionality, differential item functioning (DIF), and local dependence, we extensively tested the performance of several MAT-CAT measures and compared their performances with a fixed format. RESULTS: Operationally, the MAT-CAT was sufficiently unidimensional and had acceptable levels of local independence. One DIF item was removed. Most importantly, the CAT measures showed that even starting with a single fixed item at the mean ability, the adaptive version delivered better performance than the fixed format in terms of several criteria including the standard error of estimate. CONCLUSION: The MAT-CAT demonstrated satisfactory psychometric properties and superior performance to a fixed format. The video-animation-based adaptive instrument can be used for assessing mobility with specificity and precision.
    Quality of Life Research 01/2013; · 2.30 Impact Factor
  • Article: 2009-2010 seasonal influenza vaccination coverage among college students from 8 universities in north Carolina.
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    ABSTRACT: Abstract Objective: The authors sought to describe the 2009-2010 seasonal influenza vaccine coverage of college students. Participants: A total of 4,090 college students from 8 North Carolina universities participated in a confidential, Web-based survey in October-November 2009. Methods: Associations between self-reported 2009-2010 seasonal influenza vaccination and demographic characteristics, campus activities, parental education, and e-mail usage were assessed by bivariate analyses and by a mixed-effects model adjusting for clustering by university. Results: Overall, 20% of students (range 14%-30% by university) reported receiving 2009-2010 seasonal influenza vaccine. Being a freshman, attending a private university, having a college-educated parent, and participating in academic clubs/honor societies predicted receipt of influenza vaccine in the mixed-effects model. Conclusions: The self-reported 2009-2010 influenza vaccine coverage was one-quarter of the 2020 Healthy People goal (80%) for healthy persons 18 to 64 years of age. College campuses have the opportunity to enhance influenza vaccine coverage among its diverse student populations.
    Journal of American College Health 12/2012; 60(8):541-7. · 1.45 Impact Factor
  • Article: Physical Activity Increases Gains in and Prevents Loss of Physical Function: Results From the Lifestyle Interventions and Independence for Elders Pilot Study.
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    ABSTRACT: BACKGROUND: Physical activity (PA) appears to have a positive effect on physical function, however, studies have not examined multiple indices of physical function jointly nor have they conceptualized physical functioning as a state rather than a trait. METHODS: About 424 men and women aged 70-89 were randomly assigned to complete a PA or a successful aging (SA) education program. Balance, gait speed, chair stand performance, grip strength, and time to complete the 400-m walk were assessed at baseline and at 6 and 12 months. Using hidden Markov model, empiric states of physical functioning were derived based on these performance measures of balance, strength, and mobility. Rates of gain and loss in physical function were compared between PA and SA. RESULTS: Eight states of disability were identified and condensed into four clinically relevant states. State 1 represented mild disability with physical functioning, states 2 and 3 were considered intermediate states of disability, and state 4 severe disability. About 30.1% of all participants changed states at 6 months, 24.1% at 12 months, and 11.0% at both time points. The PA group was more likely to regain or sustain functioning and less likely to lose functioning when compared with SA. For example, PA participants were 20% more likely than the SA participants to remain in state 1. CONCLUSION: PA appears to have a favorable effect on the dynamics of physical functioning in older adults.
    The Journals of Gerontology Series A Biological Sciences and Medical Sciences 09/2012; · 4.60 Impact Factor
  • Article: Impact of a randomized campus/community trial to prevent high-risk drinking among college students.
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    ABSTRACT: High-risk drinking by college students continues to pose a significant threat to public health. Despite increasing evidence of the contribution of community-level and campus-level environmental factors to high-risk drinking, there have been few rigorous tests of interventions that focus on changing these interlinked environments. The Study to Prevent Alcohol Related Consequences (SPARC) assessed the efficacy of a comprehensive intervention using a community organizing approach to implement environmental strategies in and around college campuses. The goal of SPARC was to reduce high-risk drinking and alcohol-related consequences among college students. Ten universities in North Carolina were randomized to an Intervention or Comparison condition. Each Intervention school was assigned a campus/community organizer. The organizer worked to form a campus-community coalition, which developed and implemented a strategic plan to use environmental strategies to reduce high-risk drinking and its consequences. The intervention was implemented over a period of 3 years. Primary outcome measures were assessed using a web-based survey of students. Measures of high-risk drinking included number of days alcohol was consumed, number of days of binge drinking, and greatest number of drinks consumed (all in the past 30 days); and number of days one gets drunk in a typical week. Measures of alcohol-related consequences included indices of moderate consequences due to one's own drinking, severe consequences due to one's own drinking, interpersonal consequences due to others' drinking, and community consequences due to others' drinking (all using a past 30-day time frame). Measure of alcohol-related injuries included (i) experiencing alcohol-related injuries and (ii) alcohol-related injuries caused to others. We found significant decreases in the Intervention group compared with the Comparison group in severe consequences due to students' own drinking and alcohol-related injuries caused to others. In secondary analyses, higher levels of implementation of the intervention were associated with reductions in interpersonal consequences due to others' drinking and alcohol-related injuries caused to others. A community organizing approach promoting implementation of environmental interventions can significantly affect high-risk drinking and its consequences among college students.
    Alcoholism Clinical and Experimental Research 07/2012; 36(10):1767-78. · 3.34 Impact Factor
  • Article: Social integration and diabetes management among rural older adults.
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    ABSTRACT: To describe diabetes management behaviors and social integration among older adults, and delineate the associations of social integration with diabetes management behaviors. Interview data from 563 African American, American Indian, and White participants (age 60+) from eight south central North Carolina counties selected using a site-based procedure. Statistical analysis comprises descriptive statistics, bivariate analysis, and multivariate analysis. Participants had high levels of social integration and largely adhered to diabetes management behaviors (glucose monitoring, checking feet, maintaining diet, formal exercise program, health provider monitoring A1C and examining feet). Social integration was associated with several behaviors; social network size, particularly other relatives seen and spoken with on the telephone, was associated with provider A1C monitoring and foot examinations. Social integration had small but significant associations with diabetes management behaviors. This analysis suggests specific mechanisms for how social integration influences the effect of disease on disability.
    Journal of Aging and Health 07/2012; 24(6):899-922. · 1.56 Impact Factor
  • Article: Comparing Two Questionnaires for Eliciting CAM Use in a Multi-Ethnic US Population of Older Adults.
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    ABSTRACT: INTRODUCTION: The NAFKAM International CAM Questionnaire (I-CAM-Q) was designed to facilitate cross-study comparisons of CAM usage. This research presents the first empirical study of the I-CAM-Q's performance. MATERIALS AND METHODS: Data were collected in two studies in a multi-ethnic (African American, American Indian, and white) population of older adults in the US. In 2010, 564 adults 60+ years were recruited. The I-CAM-Q was interviewer-administered. Data were compared to those collected in 2002 from a random sample of 701 Medicare recipients 65+ years. The 2002 survey included an extensive inventory of specific CAM therapies derived from local ethnographic research. Comparisons of the responses for 14 CAM modalities common to the two studies used logistic regression adjusted for demographics. RESULTS: There were no significant differences between the 2002 and 2010 surveys in the proportions reporting 10 modalities, including use of chiropractors, homeopaths, acupuncturists, herbalists, spiritual healers, vitamins, minerals, homeopathic remedies, Qigong, visualization, and prayer for health. Significantly less use of physicians and more use of relaxation techniques were reported in 2010. Herb use and garlic, as a specific herb, were reported significantly less in 2010. CONCLUSIONS: Overall, the I-CAM-Q obtained results similar to those produced by a population-specific questionnaire. Those differences observed appear to reflect differences in the studies' inclusion criteria or secular trends in CAM. This study supports the intention of the I-CAM-Q to substitute for local and regional surveys in order to allow cross-study comparisons of CAM use. Further tests, preferably through contemporaneous data collection are needed in other populations.
    European journal of integrative medicine. 06/2012; 4(2):e205-e211.
  • Article: The association of mental conditions with blood glucose levels in older adults with diabetes.
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    ABSTRACT: Objectives: People with diabetes must engage in several self-care activities to manage blood glucose; cognitive function and other affective disorders may affect self-care behaviors. We examined the executive function domain of cognition, depressive symptoms, and symptoms of generalized anxiety disorder (GAD) to determine which common mental conditions can co-occur with diabetes are associated with blood glucose levels. Methods: We conducted a cross-sectional in-person survey of 563 rural older adults (age 60 years or older) with diabetes that included African Americans, American Indians, and Whites from eight counties in south-central North Carolina. Hemoglobin A1C (A1C) was measured from a finger-stick blood sample to assess blood glucose control. Executive function, depressive symptoms, and symptoms of GAD were assessed using established measures and scoring procedures. Separate multivariate linear regression models were used to examine the association of executive function, depressive symptoms, and symptoms of GAD with A1C. Results: Adjusting for potential confounders including age, gender, education, ethnicity, marital status, history of stroke, heart disease, hypertension, diabetes knowledge, and duration of diabetes, executive function was significantly associated with A1C levels: every one-unit increase in executive function was associated with a 0.23 lower A1C value (p = 0.02). Symptoms of depression and GAD were not associated with A1C levels. Conclusions: Low executive function is potentially a barrier to self-care, the cornerstone of managing blood glucose levels. Training aids that compensate for cognitive impairments may be essential for achieving effective glucose control.
    Aging and Mental Health 05/2012; 16(8):950-7. · 1.37 Impact Factor
  • Article: Using graded response model for the prediction of prostate cancer risk.
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    ABSTRACT: Disease risk-associated single nucleotide polymorphisms (SNPs) identified from genome-wide association studies (GWAS) have the potential to be used for disease risk prediction. An important feature of these risk-associated SNPs is their weak individual effect but stronger cumulative effect on disease risk. To date, a stable summary estimate of the joint effect of genetic variants on disease risk prediction is not available. In this study, we propose to use the graded response model (GRM), which is based on the item response theory, for estimating the individual risk that is associated with a set of SNPs. We compare the GRM with a recently proposed risk prediction model called cumulative relative risk (CRR). Thirty-three prostate cancer risk-associated SNPs were originally discovered in GWAS by December 2009. These SNPs were used to evaluate the performance of GRM and CRR for predicting prostate cancer risk in three GWAS populations, including populations from Sweden, Johns Hopkins Hospital, and the National Cancer Institute Cancer Genetic Markers of Susceptibility study. Computational results show that the risk prediction estimates of GRM, compared to CRR, are less biased and more stable.
    Human Genetics 03/2012; 131(8):1327-36. · 5.07 Impact Factor
  • Article: Lifestyle change and mobility in obese adults with type 2 diabetes.
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    ABSTRACT: Adults with type 2 diabetes mellitus often have limitations in mobility that increase with age. An intensive lifestyle intervention that produces weight loss and improves fitness could slow the loss of mobility in such patients. We randomly assigned 5145 overweight or obese adults between the ages of 45 and 74 years with type 2 diabetes to either an intensive lifestyle intervention or a diabetes support-and-education program; 5016 participants contributed data. We used hidden Markov models to characterize disability states and mixed-effects ordinal logistic regression to estimate the probability of functional decline. The primary outcome was self-reported limitation in mobility, with annual assessments for 4 years. At year 4, among 2514 adults in the lifestyle-intervention group, 517 (20.6%) had severe disability and 969 (38.5%) had good mobility; the numbers among 2502 participants in the support group were 656 (26.2%) and 798 (31.9%), respectively. The lifestyle-intervention group had a relative reduction of 48% in the risk of loss of mobility, as compared with the support group (odds ratio, 0.52; 95% confidence interval, 0.44 to 0.63; P<0.001). Both weight loss and improved fitness (as assessed on treadmill testing) were significant mediators of this effect (P<0.001 for both variables). Adverse events that were related to the lifestyle intervention included a slightly higher frequency of musculoskeletal symptoms at year 1. Weight loss and improved fitness slowed the decline in mobility in overweight adults with type 2 diabetes. (Funded by the Department of Health and Human Services and others; ClinicalTrials.gov number, NCT00017953.).
    New England Journal of Medicine 03/2012; 366(13):1209-17. · 53.30 Impact Factor
  • Article: Screening and brief intervention for tobacco use by student health providers on college campuses.
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    ABSTRACT: This study assessed college students' reports of tobacco screening and brief intervention by student health center providers. Participants were 3,800 students from 8 universities in North Carolina. Web-based survey of a stratified random sample of undergraduates. Fifty-three percent reported ever visiting their student health center. Of those, 62% reported being screened for tobacco use. Logistic regression revealed screening was higher among females and smokers, compared to nonsmokers. Among students who were screened and who reported tobacco use, 50% reported being advised to quit or reduce use. Brief intervention was more likely among current daily smokers compared to current nondaily smokers, as well as at schools with higher smoking rates. Screening and brief intervention were more likely at schools with lower clinic caseloads. Results highlight the need to encourage college health providers to screen every patient at every visit and to provide brief intervention for tobacco users.
    Journal of American College Health 01/2012; 60(1):66-73. · 1.45 Impact Factor
  • Article: Performance of health literacy tests among older adults with diabetes.
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    ABSTRACT: Knowing a patient's health literacy can help clinicians and researchers anticipate a patient's ability to understand complex health regimens and deliver better patient-centered instructions and information. Poor health literacy has been linked with lower ability to function adequately in health care systems. We evaluated and compared three measures of health literacy and performance among older patients with diabetes. Cross-sectional study utilizing in-person interviews conducted in participants' homes. A tri-ethnic sample (n = 563) of African American, American Indian, and white older adults with diabetes from eight counties in south-central North Carolina. Participants completed interviews and health literacy assessments using the Short-Form Test of Functional Health Literacy in Adults (S-TOFHLA), the Rapid Estimates of Adult Literacy in Medicine Short-Form (REALM-SF), or the Newest Vital Signs (NVS). Scores for reading comprehension and numeracy were calculated. Over 90% completed the S-TOFHLA numeracy and approximately 85% completed the S-TOFHLA reading and REALM-SF. Only 73% completed the NVS. The correlation of S-TOFHLA total scores with REALM-SF and NVS were 0.48 and 0.54, respectively. Age, gender, ethnic, educational and income differences in health literacy emerged for several instruments, but the pattern of results across the instruments was highly variable. A large segment of older adults is unable to complete short-form assessments of health literacy. Among those who were able to complete assessments, the REALM-SF and NVS performed comparably, but their relatively low convergence with the S-TOFHLA raises questions about instrument selection when studying health literacy of older adults.
    Journal of General Internal Medicine 11/2011; 27(5):534-40. · 2.83 Impact Factor
  • Article: Older adults' common sense models of diabetes.
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    ABSTRACT: To investigate the importance of viewing belief systems about health maintenance holistically. Qualitative (N=74) and quantitative data (N=95) were obtained from a multi-ethnic rural-dwelling sample of older adults with diabetes to characterize their common sense models (CSMs) of diabetes. There is a discrete number of CSMs held by older adults, each characterized by unique clusters of diabetes-related knowledge and beliefs. Individuals whose CSM was shaped by biomedical knowledge were better able to achieve glycemic control. Viewing individuals' health beliefs incrementally or in a piece-meal strategy may be less effective for health behavior change than focusing on beliefs holistically.
    American journal of health behavior 05/2011; 35(3):318-33. · 1.31 Impact Factor
  • Article: Evaluation of free to grow: head start partnerships to promote substance-free communities.
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    ABSTRACT: Free to Grow: Head Start Partnerships to Promote Substance-free Communities (FTG) was a national initiative in which local Head Start (HS) agencies, in partnership with other community organizations, implemented a mix of evidence-based family-strengthening and community-strengthening strategies. The evaluation of FTG used a quasi-experimental design to compare 14 communities that participated in the FTG intervention with 14 matched comparison communities. Telephone surveys were conducted with two cohorts of the primary caregivers of children in HS at baseline and then annually for 2 years. The survey was also administered to repeated cross-sectional samples of primary caregivers of young children who were not enrolled in HS. No consistent evidence was found in changes in family functioning or neighborhood conditions when the 14 FTG sites were compared to 14 matched sites. However, caregivers of young children who were not in HS in three high-implementing FTG sites showed evidence of improvements in neighborhood organization, neighborhood norms against substance abuse, and child disciplinary practices. Results provide highly limited support for the concept that family and neighborhood conditions that are likely to affect child development and well-being can be changed through organized efforts implemented by local HS programs.
    Evaluation Review 04/2011; 35(2):153-88. · 1.20 Impact Factor
  • Article: Blood glucose symptom recognition: perspectives of older rural adults.
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    ABSTRACT: Blood glucose symptom recognition and the interpretation of how one feels with regard to low or high glucose can impact how diabetes is self-managed. Understanding interpretation of symptoms related to diabetes and ultimate glucose regulation can be challenging. Health care providers can develop strategies to improve care by listening to individuals describe their symptoms in the context of everyday life. The perspectives of older rural adults were assessed through individual in-depth interviews conducted among 75 African American, American Indian, and white individuals. The study design included a sample balanced with regard to sex, ethnicity, and educational attainment. The Self-Regulatory Model of Illness and the concept that people construct their own common sense models of health were utilized in this study. There were four dominant themes of symptoms described that were related to blood glucose. These categories included sensations, lightheadedness, energy level, and eyesight changes. Participants described symptoms they experienced at perceived levels of both high and low blood glucose. Results suggest that older adults were unable to distinguish whether their symptoms occurred because of high or low blood glucose. Education that incorporates methods to aid older individuals differentiate blood glucose levels related to diabetes symptoms could help improve self-management.
    The Diabetes Educator 03/2011; 37(3):363-9. · 1.96 Impact Factor
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    Article: Using video animation to assess mobility in older adults.
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    ABSTRACT: Although the importance of the context of task performance in the assessment of mobility in older adults is generally understood, there is little empirical evidence that demonstrates how sensitive older adults are to subtle changes in task demands. Thus, we developed a novel approach to examine this issue. We collected item response data to 81 animated video clips, where various mobility-related tasks were modified in a systematic fashion to manipulate task difficulty. The participants (N = 234), 166 women and 68 men, had an average age of 81.9 years and a variety of comorbidities. Histograms of item responses revealed dramatic and systematic effects on older adults' self-reported ability when varying walking speed, use of a handrail during ascent and descent of stairs, walking at different speeds outdoors over uneven terrain, and carrying an object. For example, there was almost a threefold increase in reporting the inability to walk at the fast speed compared with the slow speed for a minute or less, and twice as many participants reported the inability to walk at the fast speed outdoors over uneven terrain compared with indoors. The data provide clear evidence that varying the contextual features and demands of a simple task such as stair climbing has a significant impact on older adults' self-reporting of ability related to mobility. More work is needed on the psychometric properties of such assessments and to determine if this methodology has conceptual and clinical relevance in studying mobility disability.
    The Journals of Gerontology Series A Biological Sciences and Medical Sciences 02/2011; 66(2):217-27. · 4.60 Impact Factor
  • Article: Changing overweight Latino preadolescent body mass index: the effect of the parent-child dyad.
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    ABSTRACT: Latino children are disproportionately burdened by obesity. To assess whether body mass index (BMI) change in preadolescents reflected that of their participating parent. A total of 72 Latino overweight/obese preadolescents (BMI ≥ 85%) and a parent participated in a randomized controlled trial. The intervention group received 5 monthly 60-minute sessions at a recreation center (group physical activity, goal setting). The control group received 2 standard-of-care clinic visits plus a group discussion. Between baseline and 6-month follow-up, 47% of children (mean change = -0.37, SD = 2.48) and 63% of parents (mean change = -0.88, SD = 3.53) decreased their BMI. Parent-child dyad BMI change was significantly correlated (r = .53, P = .001). In linear modeling, those preadolescents in the control group were more likely to lose absolute BMI units (-0.96, P = .03); whereas those who had parents who gained BMI over the time interval were more likely to increase their BMI (0.17, P = .008). Obesity interventions should focus on the parent-child dyad.
    Clinical Pediatrics 01/2011; 50(1):29-36. · 1.15 Impact Factor
  • Article: Comparison of intraclass correlation coefficient estimates and standard errors between using cross-sectional and repeated measurement data: the Safety Check cluster randomized trial.
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    ABSTRACT: Designing cluster randomized trials in clinical studies often requires accurate estimates of intraclass correlation, which quantifies the strength of correlation between units, such as participants, within a cluster, such as a practice. Published ICC estimates, even when available, often suffer from the problem of wide confidence intervals. Using data from a national, randomized, controlled study concerning violence prevention for children--the Safety Check--we compare the ICC values derived from two approaches only baseline data and using both baseline and follow-up data. Using a variance component decomposition approach, the latter method allows flexibility in handling complex data sets. For example, it allows for shifts in the outcome variable over time and for an unbalanced cluster design. Furthermore, we evaluate the large-sample formula for ICC estimates and standard errors using the bootstrap method. Our findings suggest that ICC estimates range from 0.012 to 0.11 for providers within practice and range from 0.018 to 0.11 for families within provider. The estimates derived from the baseline-only and repeated-measurements approaches agree quite well except in cases in which variation over repeated measurements is large. The reductions in the widths of ICC confidence limits from using repeated measurement over baseline only are, respectively, 62% and 42% at the practice and provider levels. The contribution of this paper therefore includes two elements, which are a methodology for improving the accuracy of ICC, and the reporting of such quantities for pediatric and other researchers who are interested in designing clustered randomized trials similar to the current study.
    Contemporary clinical trials 11/2010; 32(2):225-32. · 1.51 Impact Factor
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    Article: Evaluation of the late life disability instrument in the Lifestyle Interventions and Independence for Elders Pilot (LIFE-P) study.
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    ABSTRACT: The late life disability instrument (LLDI) was developed to assess limitations in instrumental and management roles using a small and restricted sample. In this paper we examine the measurement properties of the LLDI using data from the Lifestyle Interventions and Independence for Elders Pilot (LIFE-P) study. LIFE-P participants, aged 70-89 years, were at elevated risk of disability. The 424 participants were enrolled at the Cooper Institute, Stanford University, University of Pittsburgh, and Wake Forest University. Physical activity and successful aging health education interventions were compared after 12-months of follow-up. Using factor analysis, we determined whether the LLDI's factor structure was comparable with that reported previously. We further examined how each item related to measured disability using item response theory (IRT). The factor structure for the limitation domain within the LLDI in the LIFE-P study did not corroborate previous findings. However, the factor structure using the abbreviated version was supported. Social and personal role factors were identified. IRT analysis revealed that each item in the social role factor provided a similar level of information, whereas the items in the personal role factor tended to provide different levels of information. Within the context of community-based clinical intervention research in aged populations, an abbreviated version of the LLDI performed better than the full 16-item version. In addition, the personal subscale would benefit from additional research using IRT. The protocol of LIFE-P is consistent with the principles of the Declaration of Helsinki and is registered at http://www.ClinicalTrials.gov (registration # NCT00116194).
    Health and Quality of Life Outcomes 10/2010; 8:115. · 2.11 Impact Factor
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    Article: Development and validation of a video-animated tool for assessing mobility.
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    ABSTRACT: Existing self-report measures of mobility ignore important contextual features of movement and require respondents to make complex judgments about specific tasks. Thus, we describe the development and validation of a short form (sf) video-animated tool for assessing mobility, the Mobility Assessment Tool-MAT-sf. This study involves cross-sectional and longitudinal analyses examining the measurement properties of the MAT-sf. The MAT-sf consists of 10 animated video clips that assess respondents' level of proficiency in performing each task. The main outcome measures used for validation included the Pepper Assessment Tool for Disability (PAT-D), the Short Physical Performance Battery (SPPB), and 400-m walk test. Participants (n = 234), 166 women and 68 men, had an average age of 81.9 years and a variety of comorbidities with 65.4% having high blood pressure. An average SPPB score of 8.6 (range 2-12) suggests that the study sample had evidence of compromised physical function but was quite heterogeneous. The MAT-sf had good content validity, excellent test-retest reliability (r = .93), and criterion-related validity with the PAT-D. Moreover, the MAT-sf added considerable variance to the prediction of both SPPB scores and 400-m gait speed over and above the PAT-D mobility subscale. The MAT-sf also discriminated between older adults who completed or failed the 400-m walk test. The MAT-sf is an innovative psychometrically sound measure of mobility. It has utility in epidemiological studies, translational science, and clinical practice.
    The Journals of Gerontology Series A Biological Sciences and Medical Sciences 06/2010; 65(6):664-71. · 4.60 Impact Factor

Institutions

  • 2008–2013
    • Wake Forest School of Medicine
      • • Department of Biostatistical Sciences
      • • Department of Pediatrics
      • • Department of Family & Community Medicine
      Winston-Salem, NC, USA
  • 2011
    • Vanderbilt University
      • Department of Pediatrics
      Nashville, MI, USA
  • 2007
    • Wake Forest University
      • Department of Biostatistical Sciences
      Winston-Salem, NC, USA