Search tips
Search criteria

Results 1-25 (39)

Clipboard (0)

Select a Filter Below

more »
Year of Publication
Document Types
1.  Unreliable Item or Inconsistent Person? A study of variation in health beliefs and belief- anchors to biomedical models 
Journal of health psychology  2013;20(8):1049-1059.
Several models for health beliefs grounded in social theories have been extensively used in health-related research. However, the measurement of beliefs, especially the stability of beliefs, is still an understudied area. For example, reliability of an item designed to measure health belief is often confounded with response consistency at the person level, and the problem is often ignored in social research in medicine. To delineate discordant responses to the same item of belief in diabetes, which could be due to item unreliability or to respondent inconsistency, we applied contemporary measurement methods to an inventory of common sense beliefs about diabetes and tested the hypothesis that individuals whose health beliefs are congruent with a biomedical model are more consistent in their item responses. Approximately equal numbers of Whites, African Americans, and American Indians (total N=563) with diabetes were recruited into the study from rural areas in North Carolina. The Common Sense Model of Diabetes Inventory, which contained 31 items across six clinical domains, was administered to the participants at baseline and then one month later. Concordance between responses was analyzed using item response theory. Item-level analysis revealed that items in the domains of Causes of Diabetes and Medical Management of Diabetes were less reliable compared to items from other domains. Person-level analysis showed that respondents who held views congruent with the biomedical model were more consistent than people who did not. Item response theory facilitates a process to evaluate item unreliability and differences in distinguishing response consistency. People with diabetes who had beliefs regarding diabetes not congruent with the biomedical model tended to be less stable in their beliefs and should be more amenable to diabetes education and other interventions.
PMCID: PMC4004728  PMID: 24170016
diabetes; common sense model; reliability; concordance; response consistency; item response theory
2.  Physical Activity Increases Gains in and Prevents Loss of Physical Function: Results From the Lifestyle Interventions and Independence for Elders Pilot Study 
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.
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.
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.
PA appears to have a favorable effect on the dynamics of physical functioning in older adults.
PMCID: PMC3593616  PMID: 22987794
Older adults; Physical activity; Randomized controlled trial; Physical functioning; Transitional states.
3.  Social Influences on Self-Reported Physical Activity in Overweight Latino Children 
Clinical pediatrics  2008;47(8):797-802.
Psychosocial variables influence physical activity for different age groups, sex, and ethnic groups. However, little is known about their influence on physical activity in preadolescent Latino children. The authors examined how a) confidence in one's ability to be physically active (self-efficacy); b) ideas about the consequences of being physically active (beliefs), and c) the influences of family and friends on physical activity (social influences) effect physical activity levels in overweight (body mass index ≥85%) Latino preadolescent children. One hundred and fourteen preadolescents participated in a larger intervention designed to improve healthy lifestyles for Latino families. The authors report baseline data collected at a community-based primary care clinic. Multivariate regression analyses showed that only social influences significantly predicted (P < .01) the metabolic equivalent adjusted self-reported baseline physical activity. Prevention and intervention strategies that augment social influences on physical activity are likely to result in more physical activity and improved health in these children.
PMCID: PMC4486014  PMID: 18539872
social influences; body mass index; obesity; Hispanic Americans
4.  Is Office-Based Counseling About Media Use, Timeouts, and Firearm Storage Effective? Results From a Cluster-Randomized, Controlled Trial 
Pediatrics  2008;122(1):e15-e25.
The objective of this study was to determine whether patients' families' violence-prevention behaviors would be affected by their primary care practitioner's use of a violence-prevention clinical intervention during the routine well-child examination.
In this cluster-randomized, controlled trial (2002–2006), 137 Pediatric Research in Office Settings practices were randomly assigned and initiated patient recruitment for either an office-based violence-prevention intervention or a control group (educational handout on literacy promotion provided). Primary caregivers of children who were aged 2 to 11 years and presented for a well-child visit were surveyed at baseline and 1 and 6 months. Practitioners were trained to (1) review a parent previsit summary regarding patient-family behavior and parental concern about media use, discipline strategies, and children's exposure to firearms, (2) counsel using brief principles of motivational interviewing, (3) identify and provide local agency resources for anger and behavior management when indicated, and (4) instruct patient-families on use of tangible tools (minute timers to monitor media time/timeouts and firearm cable locks to store firearms more safely where children live or play). Main outcomes were change over time in self-reported media use < 120 minutes per day, use of timeouts, and use of firearm cable locks.
Generalized estimating equation analysis revealed a significant effect at 6 months for decreased media use and safer firearm storage. The intervention group compared with the control group showed an increase in limiting media use to < 120 minutes per day. There was no significant effect for timeout use. There was a substantial increase in storing firearms with cable locks for the intervention group versus a decrease for the control group.
This randomized, controlled trial demonstrated decreased media exposure and increased safe firearm storage as a result of a brief office-based violence-prevention approach.
PMCID: PMC4486046  PMID: 18595960
randomized; controlled trial; violence prevention; primary care; effect
5.  Transition to Sarcopenia and Determinants of Transitions in Older Adults: A Population-Based Study 
Diagnostic criteria for sarcopenia from appendicular lean mass (ALM), strength, and performance have been proposed, but little is known regarding the progression of sarcopenia.
We examined the time course of sarcopenia and determinants of transitioning toward and away from sarcopenia.
ALM, gait speed, and grip strength were assessed seven times over 9 years in 2,928 initially well-functioning adults aged 70–79. Low ALM was defined as less than 7.95 kg/m2 (men) or less than 6.24 kg/m2 (women), low performance as gait speed less than 1.0 m/s, low strength as grip strength less than 30 kg (men) or less than 20 kg (women). Presarcopenia was defined as low ALM and sarcopenia as low ALM with low performance or low strength. Hidden Markov modeling was used to characterize states of ALM, strength, and performance and model transitions leading to sarcopenia and death. Determinants of transitioning toward and away from sarcopenia were examined with logistic regression.
Initially, 54% of participants had normal ALM, strength, and performance; 21% had presarcopenia; 5% had sarcopenia; and 20% had intermediate characteristics. Of participants with normal ALM, strength, and performance, 1% transitioned to presarcopenia and none transitioned to sarcopenia. The greatest transition to sarcopenia (7%) was in presarcopenic individuals. Low-functioning and sarcopenia states were more likely to lead to death (12% and 13%). Higher body mass index (p < .001) and pain (p = .05) predicted transition toward sarcopenia, whereas moderate activity predicted transition from presarcopenia to more normal states (p = .02).
Pain, physical activity, and body mass index, potentially modifiable factors, are determinants of transitions. Promotion of health approaching old age is important as few individuals transition away from their initial state.
PMCID: PMC4022098  PMID: 24013673
Muscle; Aging; Physical function; Sarcopenia; Epidemiology.
6.  Obesity Influences Transitional States of Disability in Older Adults With Knee Pain 
This study employed relatively new statistical methods to understand how many states are needed to describe disability in older adults with knee pain, describe the relative probability of transitioning between states over time, and examine whether obesity influences the probability of transitioning between states.
Prospective epidemiologic study of older adults with knee pain.
The participants, 245 women and 235 men, were 65 years or older, had chronic knee pain on most days, and had difficulty with at least 1 mobility-related activity caused by knee pain.
Not applicable.
Main Outcome Measure
The primary instrument, the Pepper Assessment Tool for Disability, evaluated self-reported difficulty with mobility, basic activities of daily living (ADLs), and instrumental activities of daily living (IADLs).
The Hidden Markov Model yielded 6 states reflecting changes in mobility, ADLs, and IADLs. There is evidence that loss in more demanding mobility-related activities such as stair climbing is an early sign for the onset of disability and that functional deficits in the lower extremities are critical to the early loss of ADLs. Overall the trend is for older adults to experience greater progression than regression and for obesity to be important in understanding severe states of disability.
These data provide a strong rationale for characterizing disability on a continuum and underscore the fluid nature of disability in older adults. As expected, lower-extremity function plays a key role in the disablement process; obesity is also particularly relevant to understanding severe states of disability.
PMCID: PMC4427514  PMID: 18996238
Aged; Obesity; Rehabilitation
7.  Psychometric properties of a computerized adaptive test for assessing mobility in older adults using novel video-animation technology 
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).
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.
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.
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.
PMCID: PMC4418556  PMID: 23334945
Mobility Assessment Tool; Item response theory; Health-related quality of life; Mobility disability; Animation
8.  Comparison of risks of cardiovascular events in the elderly using standard survival analysis and multiple-events and recurrent-events methods 
Epidemiological studies about cardiovascular diseases often rely on methods based on time-to-first-event for data analysis. Without taking into account multiple event-types and the recurrency of a specific cardiovascular event, this approach may underestimate the overall cardiovascular burden of some risk factors, if that is the goal of the study.
In this study we compare four different statistical approaches, all based on the Weibull distribution family of survival model, in analyzing cardiovascular risk factors. We use data from the Cardiovascular Health Study as illustration. The four models respectively are time-to-first-event only, recurrent-events only, multiple-event-types only, and joint recurrent and multiple-event-type models.
Although the four models produce consistent results regarding the significance of the risk factors, the magnitude of the hazard ratios and their confidence intervals are different. The joint model produces hazard ratios that are substantially higher than the time-to-first-event model especially for the risk factors of smoking and diabetes.
Our findings suggest that for people with diabetes and are currently smoking, the overall cardiovascular burden of these risk factors would be substantially higher than that estimated using time-to-first-event method.
Electronic supplementary material
The online version of this article (doi:10.1186/s12874-015-0004-3) contains supplementary material, which is available to authorized users.
PMCID: PMC4364095  PMID: 25887387
Cardiovascular disease; Cardiovascular risk factor; Survival analysis; Weibull distribution
9.  Patterns and Stability over Time of Older Adults’ Diabetes-related Beliefs 
We sought to identify coherent profiles of diabetes beliefs within discrete domains (ie causes, symptoms, consequences, self management, and medical management), and delineate consistency of belief profiles over one month.
Diabetes beliefs of rural-dwelling older adults were assessed with the Common Sense Model of Diabetes Inventory at baseline (N = 593) and one month later (N = 563).
A discrete number of belief patterns were identified in each belief domain using latent class analysis. Belief patterns varied by the extent to which more popular or folk notions of diabetes encroached on biomedical understandings of the disease. Belief patterns were generally stable over time.
A manageable number of belief patterns can be identified and used to strengthen patient-centered care and, potentially, enhance diabetes management.
PMCID: PMC4190851  PMID: 25309938
Common Sense Model of Illness; diabetes beliefs; type 2 diabetes; older adultst
10.  The MAT-sf: Clinical Relevance and Validity 
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.
The analyses employed baseline data from the Lifestyle Interventions and Independence for Elders Study.
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/m2. 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).
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.
PMCID: PMC3814234  PMID: 23685766
Mobility; Geriatric assessment; Physical function; MAT-sf
11.  Older Adults’ Fears about Diabetes: Using Common Sense Models of Disease to Understand Fear Origins and Implications for Self-Management 
This study examines older adults’ fears of diabetes complications and their effects on self-management practices. Existing models of diabetes self-management posit that patients’ actions are grounded in disease beliefs and experience, but there is little supporting evidence. In-depth qualitative interviews were conducted with a community-based sample of 74 African American, American Indian, and white older adults with diabetes. Analysis uses Leventhal’s Common Sense Model of Diabetes to link fears to early experience and current self-management. Sixty-three identified fears focused on complications that could limit carrying out normal activities: amputation, blindness, low blood glucose and coma, and disease progression to insulin use and dialysis. Most focused self-management on actions to prevent specific complications, rather than on managing the disease as a whole. Early experiences focused attention on the inevitability of complications and the limited ability of patients to prevent them. Addressing older adults’ fears about diabetes may improve their diabetes self-management practices.
PMCID: PMC4212900  PMID: 25364096
Rural; qualitative methods; common sense model
12.  Are Medical Students Aware of Their Anti-Obesity Bias? 
Anti-obesity prejudices affect the quality of care obese individuals receive. The authors sought to determine the prevalence of weight-related biases among medical students and whether they were aware of their biases.
Between 2008 and 2011, the authors asked all third-year medical students at Wake Forest School of Medicine to complete the Weight Implicit Association Test (IAT), a validated measure of implicit preferences for “fat” or “thin” individuals. Students also answered a semantic differential item assessing their explicit weight-related preferences. The authors determined students’ awareness of their biases by examining the correlation between students’ explicit preferences and their IAT scores.
Of 354 medical students, 310 (88%) completed valid surveys and consented to participate. Overall, 33% (101/310) self-reported a significant (“moderate” or “strong”) explicit anti-fat bias. No students self-reported a significant explicit anti-thin bias. According to the IAT scores, over half of students had a significant implicit weight bias: 39% (121/310) had an anti-fat bias and 17% (52/310) an anti-thin bias. Two-thirds of students (67%, 81/121) were unaware of their implicit anti-fat bias. Only male gender predicted an explicit anti-fat bias (odds ratio 3.0, 95% confidence interval 1.8 – 5.3). No demographic factors were associated with an implicit anti-fat bias. Students’ explicit and implicit biases were not correlated (Pearson r = 0.03, P = .58).
Over one-third of medical students had a significant implicit anti-fat bias; few were aware of that bias. Accordingly, medical schools’ obesity curricula should address weight-related biases and their potential impact on care.
PMCID: PMC3930920  PMID: 23702519
13.  Physical Activity of Preschool-Aged Latino Children in Farmworker Families 
To describe time spent in sedentary and moderate-to-vigorous physical activity (MVPA) by children in Latino farmworker families; and delineate sources of variation in sedentary and MVPA.
Data were from mother-child dyads (N = 248) in Latino farmworker households in North Carolina. Physical activity was assessed using accelerometers; mothers described their children’s characteristics and their physical and social environments.
Children spent 6.2 hours/day sedentary (Median=369 minutes), and 6.0 minutes/day in MVPA. Children in Head Start spent more time sedentary, whereas children living where dogs roam freely were less sedentary. Children whose mothers limited screen time spent 2 more minutes in MVPA.
Preschool-aged Latino children in farmworker families are sedentary, engaging in very little MVPA.
PMCID: PMC4060153  PMID: 24933141
preschool-aged children; Latinos; farmworkers; physical activity
14.  Applicability of the Nonverbal Learning Disability Paradigm for Children With 22q11.2 Deletion Syndrome 
Journal of learning disabilities  2012;47(2):153-166.
Chromosome 22q11.2 deletion syndrome (22q11DS) is the most common microdeletion in humans. Nonverbal learning disability (NLD) has been used to describe the strengths and deficits of children with 22q11DS, but the applicability of the label for this population has seldom been systematically evaluated. The goal of the current study was to address how well the NLD diagnosis characterizes children and adolescents with 22q11DS. A total of 74 children and adolescents with 22q11DS were given neurocognitive, socioemotional, and academic assessments to measure aspects of NLD. Of the cohort, 20% met at least 7 of 9 assessed criteria for NLD; 25% showed verbal skills exceeding their nonverbal skills as assessed by an IQ test; and 24% showed the good rote verbal capacity commonly associated with NLD. Hypothesizing that if the entire cohort did not show consistent NLD characteristics, the descriptor might be more accurate for a distinct subgroup, the authors used latent class analysis to divide participants into three subgroups. However, the lines along which the groups broke out were more related to general functioning level than to NLD criteria. All three groups showed a heightened risk for psychiatric illness, highlighting the importance of careful mental health monitoring for all children with 22q11DS.
PMCID: PMC4045450  PMID: 22572413
nonverbal learning disability; 22q11 deletion syndrome; velocardiofacial syndrome; latent class modeling
15.  Partially ordered mixed hidden Markov model for the disablement process of older adults 
At both the individual and societal levels, the health and economic burden of disability in older adults is enormous in developed countries, including the U.S. Recent studies have revealed that the disablement process in older adults often comprises episodic periods of impaired functioning and periods that are relatively free of disability, amid a secular and natural trend of decline in functioning. Rather than an irreversible, progressive event that is analogous to a chronic disease, disability is better conceptualized and mathematically modeled as states that do not necessarily follow a strict linear order of good-to-bad. Statistical tools, including Markov models, which allow bidirectional transition between states, and random effects models, which allow individual-specific rate of secular decline, are pertinent. In this paper, we propose a mixed effects, multivariate, hidden Markov model to handle partially ordered disability states. The model generalizes the continuation ratio model for ordinal data in the generalized linear model literature and provides a formal framework for testing the effects of risk factors and/or an intervention on the transitions between different disability states. Under a generalization of the proportional odds ratio assumption, the proposed model circumvents the problem of a potentially large number of parameters when the number of states and the number of covariates are substantial. We describe a maximum likelihood method for estimating the partially ordered, mixed effects model and show how the model can be applied to a longitudinal data set that consists of N = 2,903 older adults followed for 10 years in the Health Aging and Body Composition Study. We further statistically test the effects of various risk factors upon the probabilities of transition into various severe disability states. The result can be used to inform geriatric and public health science researchers who study the disablement process.
PMCID: PMC3777389  PMID: 24058222
Latent Markov model; continuation ratio model; EM algorithm; generalized linear model; Health ABC study
16.  Assessment of a Short Diabetes Knowledge Instrument for Older and Minority Adults 
The Diabetes educator  2013;40(1):68-76.
The purpose of the study was to assess the performance of a short diabetes knowledge instrument (SDKI) in a large multi-ethnic sample of older adults with diabetes and to identify possible modifications to improve its ability to document diabetes knowledge.
Research Design and Methods
A sample of 593 African American, American Indian, and white female and male adults 60 years and older, with diabetes diagnosed at least two years prior, was recruited from eight North Carolina counties. All completed an interview that included a 16-item questionnaire to assess diabetes knowledge. A subsample of 46 completed the questionnaire a second time at a subsequent interview. Item-response analysis was used to refine the instrument to well-performing items. The instrument consisting of the remaining items was subjected to analyses to assess validity and test-retest reliability.
Three items were removed after item-response analysis. Scores for the resulting instrument were lower among minority and older participants, as well as those with lower educational attainment and income. Scores for test-retest were highly correlated.
The SDKI (13 item questionnaire) appears to be a valid and reliable instrument to evaluate knowledge about diabetes. Assessment in a multi-ethnic sample of older adults suggests that this instrument can be used to measure diabetes knowledge in diverse populations. Further evaluation is needed to determine whether or not this instrument can detect changes in knowledge resulting from diabetes education or other interventions.
PMCID: PMC3946961  PMID: 24163359
17.  Neuroanatomical target theory as a predictive model for radiation-induced cognitive decline 
Neurology  2013;80(8):747-753.
In a retrospective review to assess neuroanatomical targets of radiation-induced cognitive decline, dose volume histogram (DVH) analyses of specific brain regions of interest (ROI) are correlated to neurocognitive performance in 57 primary brain tumor survivors.
Neurocognitive assessment at baseline included Trail Making Tests A/B, a modified Rey-Osterreith Complex Figure, California or Hopkins Verbal Learning Test, Digit Span, and Controlled Oral Word Association. DVH analysis was performed for multiple neuroanatomical targets considered to be involved in cognition. The %v10 (percent of ROI receiving 10 Gy), %v40, and %v60 were calculated for each ROI. Factor analysis was used to estimate global cognition based on a summary of performance on individual cognitive tests. Stepwise regression was used to determine which dose volume predicted performance on global factors and individual neurocognitive tests for each ROI.
Regions that predicted global cognitive outcomes at doses <60 Gy included the corpus callosum, left frontal white matter, right temporal lobe, bilateral hippocampi, subventricular zone, and cerebellum. Regions of adult neurogenesis primarily predicted cognition at %v40 except for the right hippocampus which predicted at %v10. Regions that did not predict global cognitive outcomes at any dose include total brain volume, frontal pole, anterior cingulate, right frontal white matter, and the right precentral gyrus.
Modeling of radiation-induced cognitive decline using neuroanatomical target theory appears to be feasible. A prospective trial is necessary to validate these data.
PMCID: PMC3589296  PMID: 23390169
18.  Predictors of posttraumatic growth in women with breast cancer 
Psycho-oncology  2013;22(12):10.1002/pon.3298.
Posttraumatic growth (PTG) is defined as ‘positive psychological change experienced as a result of a struggle with highly challenging life circumstances’. The current study examined change in PTG over 2 years following breast cancer diagnosis and variables associated with PTG over time.
Women recently diagnosed with breast cancer completed surveys within 8 months of diagnosis and 6, 12, and 18 months later. Linear mixed effects models were used to assess the longitudinal effects of demographic, medical, and psychosocial variables on PTG as measured by the Posttraumatic Growth Inventory (PTGI).
A total of 653 women were accrued (mean age = 54.9, SD = 12.6). Total PTGI score increased over time mostly within the first few months following diagnosis. In the longitudinal model, greater PTGI scores were associated with education level, longer time since diagnosis, greater baseline level of illness intrusiveness, and increases in social support, spirituality, use of active–adaptive coping strategies, and mental health. Findings for the PTGI domains were similar to those for the total score except for the Spiritual Change domain.
PTG develops relatively soon after a breast cancer diagnosis and is associated with baseline illness intrusiveness and increases in social support, spirituality, use of active–adaptive coping strategies, and mental health.
PMCID: PMC3884903  PMID: 24136875
19.  2009–2010 Seasonal Influenza Vaccination Coverage Among College Students From 8 Universities in North Carolina 
We sought to describe the 2009–2010 seasonal influenza vaccine coverage of college students.
4090 college students from eight North Carolina universities participated in a confidential, web-based survey in October-November 2009.
Associations between self-reported 2009–2010 seasonal influenza vaccination and demographic characteristics, campus activities, parental education, and email usage were assessed by bivariate analyses and by a mixed-effects model adjusting for clustering by university.
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.
The self-reported 2009–2010 influenza vaccine coverage was one-quarter of the 2020 Healthy People goal (80%) for healthy persons 18–64 years of age. College campuses have the opportunity to enhance influenza vaccine coverage among its diverse student populations.
PMCID: PMC3507424  PMID: 23157195
20.  Measuring Medical Student Attitudes and Beliefs Regarding Obese Patients 
Obesity bias has been shown to undermine the patient-doctor relationship and lead to substandard care. A valid and reliable instrument was developed to measure medical students’ attitudes and beliefs about obese patients.
The authors conducted a literature search to identify validated measures of obesity bias. Since no appropriate scale was located, the decision to design a novel survey instrument, titled the NEW (Nutrition, Exercise and Weight Management) Attitudes Scale, was made. An expert panel generated items which were then discussed in focus groups of third year medical students. Experienced medical educators served as judges, weighting the items using a Thurstone scale. Second and fourth year medical students completed these items alongside two previously validated measures of obesity bias, the Anti-Fat Attitudes Questionnaire (AFA) and Beliefs About Obese Persons Scale (BAOP). Third year students completed the NEW scales before and after a simulated encounter with an obese standardized patient instructor.
Thirty one items comprised the final instrument. A sample of 201 judges rated the positivity of items. A sample of 111 second and fourth year medical students completed the survey (mean score 24.4, range −37 to 76 out of a possible −118 to 118); Pearson correlations between AFA and BAOP were −0.47 and 0.23, respectively. Test-retest reliability was 0.89. Students scored 27% higher after completing the standardized patient-instructor encounter (P<.001).
The NEW Attitudes Scale had good validity and reliability and may be used in future studies to measure medical students’ attitudes towards obese patients.
PMCID: PMC3826984  PMID: 23269296
21.  The Association of Mental Conditions with Blood Glucose Levels in Older Adults with Diabetes 
Aging & mental health  2012;16(8):950-957.
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 that can co-occur with diabetes are associated with blood glucose levels.
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.
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.
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.
PMCID: PMC3434257  PMID: 22640032
A1C; cognitive function; depression; anxiety; aging
22.  Impact of a Randomized Campus/Community Trial to Prevent High-Risk Drinking among College Students 
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 timeframe). Measure of alcohol-related injuries included (1) experiencing alcohol-related injuries and (2) alcohol-related injuries caused to others.
We found significant decreases in the Intervention group compared to 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.
PMCID: PMC3752385  PMID: 22823091
23.  Cognitive function is a risk for health literacy in older adults with diabetes 
Cognitive impairment is common in older adults with diabetes, yet it is unclear to what extent cognitive function is associated with health literacy. We hypothesized that cognitive function, independent of education, is associated with health literacy.
The sample included 537 African American, American Indian, and White men and women 60 years or older. Measures of cognitive function included the Mini-Mental State Examination (MMSE), Verbal Fluency, Brief Attention, and Digit Span Backward tests. Health literacy was assessed using the S-TOFHLA.
Cognitive function was associated with health literacy, independent of education and other important confounders. Every unit increase in the MMSE, Digit Span Backward, Verbal Fluency or Brief Attention was associated with a 20% (p<.001), 34% (p<.001), 5% (p<.01), and 16% (p<.01) increase in the odds of having adequate health literacy, respectively.
These results suggest that cognitive function is associated with health literacy in older adults with diabetes. Because poor cognitive function may undermine health literacy, efforts to target older adults on improving health literacy should consider cognitive function as a risk factor.
PMCID: PMC3742688  PMID: 23806477
cognition; health literacy; diabetes
24.  Using graded response model for the prediction of prostate cancer risk 
Human genetics  2012;131(8):1327-1336.
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.
PMCID: PMC3734950  PMID: 22461065
25.  Design and implementation of the mobility assessment tool: software description 
In previous work, we described the development of an 81-item video-animated tool for assessing mobility. In response to criticism levied during a pilot study of this tool, we sought to develop a new version built upon a flexible framework for designing and administering the instrument.
Rather than constructing a self-contained software application with a hard-coded instrument, we designed an XML schema capable of describing a variety of psychometric instruments. The new version of our video-animated assessment tool was then defined fully within the context of a compliant XML document. Two software applications—one built in Java, the other in Objective-C for the Apple iPad—were then built that could present the instrument described in the XML document and collect participants’ responses. Separating the instrument’s definition from the software application implementing it allowed for rapid iteration and easy, reliable definition of variations.
Defining instruments in a software-independent XML document simplifies the process of defining instruments and variations and allows a single instrument to be deployed on as many platforms as there are software applications capable of interpreting the instrument, thereby broadening the potential target audience for the instrument. Continued work will be done to further specify and refine this type of instrument specification with a focus on spurring adoption by researchers in gerontology and geriatric medicine.
PMCID: PMC3729603  PMID: 23879716

Results 1-25 (39)