Nanhua Zhang - Academia.edu (original) (raw)

Papers by Nanhua Zhang

Journal of Cystic Fibrosis, 2015

Previous studies of CF treatments have shown suboptimal adherence, though little has been reporte... more Previous studies of CF treatments have shown suboptimal adherence, though little has been reported regarding adherence patterns to ivacaftor. Electronic monitoring (EM) of adherence is considered a gold standard of measurement. Adherence rates by EM were prospectively obtained and patterns over time were analyzed. EM-derived adherence rates were compared to pharmacy refill history and self-report. 12 subjects (age 6-48years; CFTR-G551D mutation) previously prescribed ivacaftor were monitored for a mean of 118days. Overall adherence by EM was 61%(SD=28%) and decreased over time. Median duration between doses was 16.9hours (IQR 13.9-24.1hours) and increased over time. There was no correlation between EM-derived adherence and either refill history (84%, r=0.26, p=0.42) or self-report (100%, r=0.40, p=0.22). Despite the promising nature of ivacaftor, our data suggest adherence rates are suboptimal and comparable to other prescribed CF therapies, and more commonly used assessments of adherence may be unreliable.

Developmental Psychology, 2016

Parent behaviors moderate the adverse consequences of pediatric traumatic brain injury (TBI); how... more Parent behaviors moderate the adverse consequences of pediatric traumatic brain injury (TBI); however, it is unknown how these moderating effects change over time. This study examined the moderating effect of observed parent behaviors over time since injury on the relation between TBI and behavioral outcomes. Participants included children, ages 3–7 years, hospitalized for moderate (n = 52) or severe (n = 20) TBI or orthopedic injury (OI; n = 95). Parent–child dyads were videotaped during structured task and free play conditions and parents completed child be-havior ratings. Linear mixed models using a lagged, time-varying moderator analysis examined the relationship of observed parent behaviors at the baseline, 6-month, and 12-month assess-ments to child behavior problems at 6 months, 12 months, and 18 months post injury, after con-trolling for pre-injury levels of child behavior problems. The effect of TBI on behavior was ex-acerbated by less favorable parent behaviors, and buffered by more favorable parent behaviors, in children with severe TBI over the first 12 months post injury. By 18 months post injury, how-ever, the moderating effect of parent behaviors diminished such that children with severe TBI showed more behavior problems relative to children with moderate TBI or OI regardless of par-ent behaviors or in response to parent behaviors that were initially protective. The results suggest that the moderating effects of the family environment are complex and likely vary in relation to both recovery and developmental factors, with potentially important implications for targets and timing of intervention.

Journal of health care for the poor and underserved, 2016

This study reports the psychometric properties and correlates of a measure of organ donation atti... more This study reports the psychometric properties and correlates of a measure of organ donation attitudes and practices for African Americans. We surveyed 736 members from 14 alumni chapters of historically African American sororities and fraternities in Michigan. We constructed subscales and compared subscale values with two variables related to donation status: 1) enrollment status in the state donor registry, and 2) intentions for future enrollment. Psychometric analyses indicated our measure tapped four distinct domains of attitudes concerning donation. The four subscales identified-General Benefits, Race Benefits, General Barriers, and Disparity Barriers-had good psychometric properties. For all four scales the more positive the attitudes toward donation held by the respondent, the more likely they were to report having signed up to be an organ donor. An understanding of attitudes toward donation may help development of effective culturally sensitive intervention messages targetin...

European Spine Journal, 2016

Journal of the International Neuropsychological Society, 2016

To examine whether apolipoprotein e4 (APOE) status moderates the association of family environmen... more To examine whether apolipoprotein e4 (APOE) status moderates the association of family environment with child functioning following early traumatic brain injury (TBI). Sixty-five children with moderate to severe TBI and 70 children with orthopedic injury (OI) completed assessments 6, 12, 18 months, and 3.5 and 6.8 years post injury. DNA was extracted from saliva samples and genotyped for APOE e4 status. Linear mixed models examined moderating effects of APOE e4 status on associations between two family environment factors (parenting style, home environment) and three child outcomes (executive functioning, behavioral adjustment, adaptive functioning). Children with TBI who were carriers of the e4 allele showed poorer adaptive functioning relative to non-carriers with TBI and children with OI in the context of low authoritarianism. At high levels of authoritarianism, non-carriers with TBI showed the poorest adaptive functioning among groups. There were no main effects or interactions involving APOE and executive functioning or behavioral adjustment. The APOE e4 allele was detrimental for long-term adaptive functioning in the context of positive parenting, whereas in less optimal parenting contexts, being a non-carrier was detrimental. We provide preliminary evidence for an interaction of APOE e4 status and parenting style in predicting long-term outcomes following early TBI. (JINS, 2016, 22, 1-6).

Brain injury, Jan 14, 2016

To compare serum biomarker levels between children with mild traumatic brain injury (mTBI) and or... more To compare serum biomarker levels between children with mild traumatic brain injury (mTBI) and orthopaedic injury (OI), acutely following injury. Secondarily, to explore the association between biomarker levels and symptom burden over 1 month post-injury. This was a prospective cohort study of children aged 11-16 years who presented to the emergency department within 6 hours of sustaining mTBI or isolated extremity OI. Serum was drawn at the time of study enrollment and levels of ubiquitin carboxyl-terminal hydrolase L1 (UCH-L1) and glial fibrillary acid protein (GFAP) were analysed. Symptom burden was assessed by the Post-Concussion Symptom Scale (PCSS) acutely following injury and at three subsequent time points over 1 month. Twenty-five children with mTBI and 20 children with OI were enrolled. The average age for the overall cohort was 13 (± 1.6) years and the majority were male and injured playing sports. GFAP levels and PCSS scores were significantly higher acutely following mT...

Journal of neurotrauma, Jan 14, 2016

The objectives of the study were to characterize long-term neuropsychological outcomes following ... more The objectives of the study were to characterize long-term neuropsychological outcomes following traumatic brain injury (TBI) sustained during early childhood and determine whether identified neuropsychological impairments mediated the effect of TBI on long-term adaptive functioning. Participants included 16 children with severe TBI, 42 children with moderate TBI, and 72 children with orthopedic injuries (OI) sustained between ages 3 and 7 years. Children completed neuropsychological tests and caregivers completed a structured interview of child adaptive functioning at 6.9 (±1.10) years post injury. Profile analysis and multiple mediator modeling were employed. Children with severe TBI demonstrated poorer fluid reasoning and inhibitory control relative to both children with moderate TBI and OI, as well as slower processing speed relative to the OI group. Both fluid reasoning and processing speed were significant independent mediators of the effect of severe TBI on adaptive functioni...

JAMA Pediatrics, 2016

Pediatric traumatic brain injury (TBI) contributes to impairments in behavior and academic perfor... more Pediatric traumatic brain injury (TBI) contributes to impairments in behavior and academic performance. However, the long-term effects of early childhood TBI on functioning across settings remain poorly understood. To examine the long-term functional outcomes of early childhood TBI relative to early childhood orthopedic injuries (OIs). We also examine the moderating role of the social environment as defined by parent report and observational measures of family functioning, parenting practices, and home environment. A prospective, longitudinal, observational cohort study conducted at each child's home, school, and hospital, including 3 children's hospitals and 1 general hospital in the Midwest. Patients were enrolled in the initial study between January 2003 and October 2006. Follow-ups were completed between January 2010 and April 2015. Fifty-eight children who sustained a TBI (67% of original enrolled cohort) and 72 children who sustained an OI (61% of the original enrolled cohort) were prospectively followed up from shortly after injury (between the ages of 3 and 7 years at enrollment) to an average of 6.7 years after injury, with assessments occurring at multiple points. Long-term functional outcomes in everyday settings, as assessed through the Child and Adolescent Functional Assessment Scale (CAFAS). Of the 130 children included, the median age for those with OIs was 11.72 years and 11.97, 12.21, and 11.72 years for those with complicated mild, moderate, and severe TBIs, respectively. Children with moderate and severe TBI were rated as having more functional impairments in multiple domains than those with OIs (P < .05). Children with complicated mild TBI had greater impairments in school (odds ratio = 2.93; 95% CI = 1.10-7.82) and with thinking (odds ratio = 15.72; 95% CI = 3.31-74.73) than those with OIs. Functional impairments in children with TBI were more pronounced among children from families with higher levels of permissive (mean CAFAS of 49.71, 35.74, 58.14, and 16.16 for severe TBI, moderate TBI, complicated mild TBI, and OI, respectively, with significant difference between severe TBI and OI [difference = 33.55; P < .001] and complicated mild TBI and OI [difference = 41.98; P < .001]) or authoritarian (mean CAFAS of 56.45, 41.80, 54.90, and 17.12 for severe TBI, moderate TBI, complicated mild TBI, and OI, respectively, with significant difference between severe TBI and OI [difference = 39.33; P < .001], moderate TBI and OI [difference = 24.68; P = .003], and complicated mild TBI and OI [difference = 37.78; P < .001]) parenting or with fewer home resources (mean CAFAS of 69.57, 47.45, 49.00, and 23.81 for severe TBI, moderate TBI, complicated mild TBI, and OI, respectively, with significant difference between severe TBI and OI [difference = 45.77; P < .001], moderate TBI and OI [difference = 23.64; P < .001], and complicated mild TBI and OI [difference = 25.20; P < .001]). Even children with relatively mild early TBI experience long-term functional impairments, particularly in the context of less favorable home environments. These findings suggest that improving parenting skills and the quality of the home environment may promote functional recovery following early TBI.

Journal of Urban Health, 2016

We assessed whether economic, legal, and social hardships were associated with human immunodefici... more We assessed whether economic, legal, and social hardships were associated with human immunodeficiency virus (HIV) risk among a sample of Black men who have sex with men (MSM) and whether associations were moderated by city of residence. The study analyzed baseline and follow-up data from HIV Prevention Trials Network 061 (N = 1553). Binary logistic regression assessed associations between hardships and HIV risk indicators. Multivariate regressions were used to test if city of residence had a moderating effect for hardships and HIV risks. Adjusted analyses showed that Black MSM with recent job loss were more likely to engage in condomless insertive anal intercourse (adjusted odds ratios (AOR) = 1.37, 95 % CI 1.01-1.87) and that those with recent financial crisis were more likely to have had two or more male sexual partners in the past 6 months (AOR = 1.65; 95 % CI 1.18-2.29). Black MSM with recent convictions were more likely to have a sexually transmitted infection at 6 months (AOR = 3.97; 95 % CI 1.58-9.94), while those who were unstably housed were more likely to have a sexually transmitted infection at 12 months (AOR = 1.71; 95 %CI 1.02 = 2.86). There were no city of residence and hardship interaction effects on HIV risks. Hardships are important factors that influence HIV risk for Black MSM. Integrating strategies that address structural factors that influence HIV risk may enhance HIV prevention interventions implementation efforts.

American journal of men's health, Jan 12, 2016

Exposure to childhood religious affiliations where the majority of members discourage homosexuali... more Exposure to childhood religious affiliations where the majority of members discourage homosexuality may have negative psychological impacts for Black men who have sex with men. This study tested the hypothesis that exposures to these environments during childhood were associated with adulthood human immunodeficiency virus (HIV)/sexually transmitted infection (STI) behavioral risk and HIV infection, because these exposures influenced HIV/STI risk by undermining race/sexual identity congruence and increasing internalized homophobia and interpersonal anxiety. Structural equation modeling as well as logistic and Poisson regressions were performed using baseline data from HIV Prevention Trials Network 061 (N = 1,553). Childhood religion affiliations that were more discouraging of homosexuality were associated with increased likelihood of HIV infection; however, the association was no longer significant after adjusting for age, income, and education. Having a childhood religion affiliatio...

Journal of Medical Statistics and Informatics, May 27, 2015

Recent work has identified the transition from adolescence to young adulthood as a period with di... more Recent work has identified the transition from adolescence to young adulthood as a period with distinct characteristics that is important for understanding of human development. Self-esteem plays a critical role in this developmental process. We use self-esteem data measured at mean ages 13, 16 and 22, and anxiety disorder diagnosis at mean age of 33 to examine the impact of development of self-esteem on onset of adult anxiety disorder. To analyze these data, we propose a Bayesian joint model with: (1) a linear mixed effects model for the longitudinal measurements, and (2) a generalized linear model for the binary primary endpoint. Our analysis indicates that the mean level of self-esteem, not the change of self-esteem, significantly predicts the onset of adult anxiety disorder. A comparison shows that the joint model yields better predictive accuracy than a two-step model. The respective area under ROC curve (AUC) is 0.60 and 0.75 for the two-step model and the joint model, respectively. The two-step estimate may be biased because this method ignores variability in the individual random effects. We conclude that joint model is the most advantageous model to analyze early life longitudinal data combined with later binary outcome. measurements and event time data. -480. | Article 36. Lin H, Turnbull BW, McCulloch CE and Slate EH. Latent class models for joint analysis of longitudinal biomarker and event process data: application to longitudinal prostate-specific antigen readings and prostate cancer. J Am Stat Assoc. 2002; 96:895-905. | Article of a linear mixed effects model for selfesteem from mean ages 13 to 22 and a generalized linear model for anxiety disorder at mean age 33. J Med Stat Inform. 2015; 3:1. http://dx.

Inquiry : a journal of medical care organization, provision and financing, 2015

Medicare Advantage was implemented in 2004 and the Recovery Audit Contractor (RAC) program was im... more Medicare Advantage was implemented in 2004 and the Recovery Audit Contractor (RAC) program was implemented in Florida during 2005. Both increase surveillance of medical necessity and deny payments for improper admissions. The purpose of the present study was to determine their potential impact on for-profit (FP) and not-for-profit (NFP) hospital operating margins in Florida. FP hospitals were expected to be more adversely affected as admissions growth has been one strategy to improve stock performance, which is not a consideration at NFPs. This study analyzed Florida community hospitals from 2000 through 2010, assessing changes in pre-tax operating margin (PTOM). Florida Agency for Health Care Administration data were analyzed for 104 community hospitals (62 FPs and 42 NFPs). Academic, public, and small hospitals were excluded. A mixed-effects model was used to assess the association of RAC implementation, organizational and payer type variables, and ownership interaction effects on...

Archives of Physical Medicine and Rehabilitation, 2015

Medicare Advantage was implemented in 2004 and the Recovery Audit Contractor (RAC) program was im... more Medicare Advantage was implemented in 2004 and the Recovery Audit Contractor (RAC) program was implemented in Florida during 2005. Both increase surveillance of medical necessity and deny payments for improper admissions. The purpose of the present study was to determine their potential impact on for-profit (FP) and not-for-profit (NFP) hospital operating margins in Florida. FP hospitals were expected to be more adversely affected as admissions growth has been one strategy to improve stock performance, which is not a consideration at NFPs. This study analyzed Florida community hospitals from 2000 through 2010, assessing changes in pre-tax operating margin (PTOM). Florida Agency for Health Care Administration data were analyzed for 104 community hospitals (62 FPs and 42 NFPs). Academic, public, and small hospitals were excluded. A mixed-effects model was used to assess the association of RAC implementation, organizational and payer type variables, and ownership interaction effects on PTOM. FP hospitals began the period with a higher average PTOM, but converged with NFPs during the study period. The average Medicare Advantage effect was not significant for either ownership type. The magnitude of the RAC variable was significantly negative for average PTOM at FPs (−4.68) and positive at NFPs (0.08), meaning RAC was associated with decreasing PTOM at FP hospitals only. RAC complements other Medicare surveillance systems that detect medically unnecessary admissions, coding errors, fraud, and abuse. Since its implementation in Florida, average FP and NFP operating margins have been similar, such that the higher margins reported for FP hospitals in the 1990s are no longer evident.

The Journal of head trauma rehabilitation, Jan 24, 2015

To elucidate the association of a functional catechol-O-methyltransferase (COMT) genotype (rs4680... more To elucidate the association of a functional catechol-O-methyltransferase (COMT) genotype (rs4680) with recovery of executive functions up to 18 months after early childhood traumatic brain injury (TBI) compared with an orthopedic injury (OI) group. Outpatient. A total of 134 children with a moderate to severe TBI (n = 63) or OI (n = 71) between the ages of 3 and 6 years who were followed 18 months postinjury. Case-comparison, longitudinal cohort MAIN MEASURES:: The Behavior Rating Inventory of Executive Function, developmental NEuroPSYchological Assessment (NEPSY) of Verbal Fluency, and a modified Stroop Test for young children (Shape School). The low-activity COMT enzyme genotype (AA) was associated with better scores on the developmental NEPSY of Verbal Fluency (F = 3.80; P = .02) and the Shape School (F = 2.89; P = .06) in all participants when controlling for injury type (TBI vs OI) over the first 18 months after injury. Injury type (TBI vs OI) did not significantly moderate th...

Research in Nursing & Health, 2015

Ghanaian men who have sex with men (MSM) have a high HIV seroprevalence, but despite a critical n... more Ghanaian men who have sex with men (MSM) have a high HIV seroprevalence, but despite a critical need to address this public health concern, research evidence has been extremely limited on influences on sexual risk behavior among MSM in Ghana. To investigate associations between HIV/STD knowledge, HIV stigma, and sexual behaviors in a sample of MSM in Ghana, we conducted a secondary data analysis of cross-sectional survey data from a non-probability sample of Ghanaian MSM (N ¼ 137). Nearly all the men (93%) had more than one current sex partner (M ¼ 5.11, SD ¼ 7.4). Of those reported partners, the average number of current female sexual partners was 1.1 (SD ¼ 2.6). Overall, knowledge levels about HIV and STDs were low, and HIV stigma was high. There was no agerelated difference in HIV stigma. Younger MSM ( 25 years) used condoms less often for anal and vaginal sex than did those over 25. Relative frequency of condom use for oral sex was lower in younger men who had higher STD knowledge and also was lower in older men who reported high HIV stigma. Knowledge and stigma were not associated with condom use for anal or vaginal sex in either age group. These descriptive data highlight the need for the development of intervention programs that address HIV/STD prevention knowledge gaps and reduce HIV stigma in Ghanaian communities. Intervention research in Ghana should address age-groupspecific HIV prevention needs of MSM youth. ß

Biometrics, 2014

There has been an increasing interest in the analysis of spatially distributed multivariate binar... more There has been an increasing interest in the analysis of spatially distributed multivariate binary data motivated by a wide range of research problems. Two types of correlations are usually involved: the correlation between the multiple outcomes at one location and the spatial correlation between the locations for one particular outcome. The commonly used regression models only consider one type of correlations while ignoring or modeling inappropriately the other one. To address this limitation, we adopt a Bayesian nonparametric approach to jointly modeling multivariate spatial binary data by integrating both types of correlations. A multivariate probit model is employed to link the binary outcomes to Gaussian latent variables; and Gaussian processes are applied to specify the spatially correlated random effects. We develop an efficient Markov chain Monte Carlo algorithm for the posterior computation. We illustrate the proposed model on simulation studies and a multidrug-resistant t...

In this study, we employed an eigenfunction decomposition algorithm associated with a Moran's coe... more In this study, we employed an eigenfunction decomposition algorithm associated with a Moran's coefficient to investigate district-level non-linearity in an empirical dataset of spatiotemporal-sampled MDR-TB parameter estimators sampled in San Juan de Lurigancho (SJL) Lima, Peru. The nonparametric technique attempted to remove the inherent autocorrelation in the model by introducing appropriate synthetic surrogate variants. We also constructed a robust Bayesian Poisson model to generate unbiased estimators for qualitatively assessing resistance to four commonly used drugs in TB treatment: isoniazid, rifampin, ethambutol, and streptomycin. Initially, data of residential addresses of individual patients with smear-positive MDR-TB were geocoded in ArcGIS. Next, the sampled data were matched automatically and interactively within the geodatabase. The MDR-TB data feature attributes were then calculated and digitally overlaid onto sub-meter resolution satellite data within a 1 km buffer of 31 georeferenced health centers using a 10 m 2 grid-based algorithm. Global autocorrelation statistics were then generated by decomposing the sampled data into positive and negative spatial filter eigenvectors using the eigenfunction decomposition algorithm. Bayesian Poisson projections were then rendered employing normal priors for each of the sampled estimators. A Residual Moran's coefficient (MC) minimization criterion was then applied to the clinical coefficients generated from the decomposition algorithm to detect any unaccounted latent autocorrelation error in the estimators. The model accounted for approximately 14% pseudo-replicated information and exhibited positive residual autocorrelation. Spatial statistics can elucidate the mechanics of MDR-TB transmission by prioritizing clinical covariates for identifying spatial distribution of high-risk populations and random heterogeneity in resistant strains.

Journal of Cystic Fibrosis, 2015

Previous studies of CF treatments have shown suboptimal adherence, though little has been reporte... more Previous studies of CF treatments have shown suboptimal adherence, though little has been reported regarding adherence patterns to ivacaftor. Electronic monitoring (EM) of adherence is considered a gold standard of measurement. Adherence rates by EM were prospectively obtained and patterns over time were analyzed. EM-derived adherence rates were compared to pharmacy refill history and self-report. 12 subjects (age 6-48years; CFTR-G551D mutation) previously prescribed ivacaftor were monitored for a mean of 118days. Overall adherence by EM was 61%(SD=28%) and decreased over time. Median duration between doses was 16.9hours (IQR 13.9-24.1hours) and increased over time. There was no correlation between EM-derived adherence and either refill history (84%, r=0.26, p=0.42) or self-report (100%, r=0.40, p=0.22). Despite the promising nature of ivacaftor, our data suggest adherence rates are suboptimal and comparable to other prescribed CF therapies, and more commonly used assessments of adherence may be unreliable.

Developmental Psychology, 2016

Parent behaviors moderate the adverse consequences of pediatric traumatic brain injury (TBI); how... more Parent behaviors moderate the adverse consequences of pediatric traumatic brain injury (TBI); however, it is unknown how these moderating effects change over time. This study examined the moderating effect of observed parent behaviors over time since injury on the relation between TBI and behavioral outcomes. Participants included children, ages 3–7 years, hospitalized for moderate (n = 52) or severe (n = 20) TBI or orthopedic injury (OI; n = 95). Parent–child dyads were videotaped during structured task and free play conditions and parents completed child be-havior ratings. Linear mixed models using a lagged, time-varying moderator analysis examined the relationship of observed parent behaviors at the baseline, 6-month, and 12-month assess-ments to child behavior problems at 6 months, 12 months, and 18 months post injury, after con-trolling for pre-injury levels of child behavior problems. The effect of TBI on behavior was ex-acerbated by less favorable parent behaviors, and buffered by more favorable parent behaviors, in children with severe TBI over the first 12 months post injury. By 18 months post injury, how-ever, the moderating effect of parent behaviors diminished such that children with severe TBI showed more behavior problems relative to children with moderate TBI or OI regardless of par-ent behaviors or in response to parent behaviors that were initially protective. The results suggest that the moderating effects of the family environment are complex and likely vary in relation to both recovery and developmental factors, with potentially important implications for targets and timing of intervention.

Journal of health care for the poor and underserved, 2016

This study reports the psychometric properties and correlates of a measure of organ donation atti... more This study reports the psychometric properties and correlates of a measure of organ donation attitudes and practices for African Americans. We surveyed 736 members from 14 alumni chapters of historically African American sororities and fraternities in Michigan. We constructed subscales and compared subscale values with two variables related to donation status: 1) enrollment status in the state donor registry, and 2) intentions for future enrollment. Psychometric analyses indicated our measure tapped four distinct domains of attitudes concerning donation. The four subscales identified-General Benefits, Race Benefits, General Barriers, and Disparity Barriers-had good psychometric properties. For all four scales the more positive the attitudes toward donation held by the respondent, the more likely they were to report having signed up to be an organ donor. An understanding of attitudes toward donation may help development of effective culturally sensitive intervention messages targetin...

European Spine Journal, 2016

Journal of the International Neuropsychological Society, 2016

To examine whether apolipoprotein e4 (APOE) status moderates the association of family environmen... more To examine whether apolipoprotein e4 (APOE) status moderates the association of family environment with child functioning following early traumatic brain injury (TBI). Sixty-five children with moderate to severe TBI and 70 children with orthopedic injury (OI) completed assessments 6, 12, 18 months, and 3.5 and 6.8 years post injury. DNA was extracted from saliva samples and genotyped for APOE e4 status. Linear mixed models examined moderating effects of APOE e4 status on associations between two family environment factors (parenting style, home environment) and three child outcomes (executive functioning, behavioral adjustment, adaptive functioning). Children with TBI who were carriers of the e4 allele showed poorer adaptive functioning relative to non-carriers with TBI and children with OI in the context of low authoritarianism. At high levels of authoritarianism, non-carriers with TBI showed the poorest adaptive functioning among groups. There were no main effects or interactions involving APOE and executive functioning or behavioral adjustment. The APOE e4 allele was detrimental for long-term adaptive functioning in the context of positive parenting, whereas in less optimal parenting contexts, being a non-carrier was detrimental. We provide preliminary evidence for an interaction of APOE e4 status and parenting style in predicting long-term outcomes following early TBI. (JINS, 2016, 22, 1-6).

Brain injury, Jan 14, 2016

To compare serum biomarker levels between children with mild traumatic brain injury (mTBI) and or... more To compare serum biomarker levels between children with mild traumatic brain injury (mTBI) and orthopaedic injury (OI), acutely following injury. Secondarily, to explore the association between biomarker levels and symptom burden over 1 month post-injury. This was a prospective cohort study of children aged 11-16 years who presented to the emergency department within 6 hours of sustaining mTBI or isolated extremity OI. Serum was drawn at the time of study enrollment and levels of ubiquitin carboxyl-terminal hydrolase L1 (UCH-L1) and glial fibrillary acid protein (GFAP) were analysed. Symptom burden was assessed by the Post-Concussion Symptom Scale (PCSS) acutely following injury and at three subsequent time points over 1 month. Twenty-five children with mTBI and 20 children with OI were enrolled. The average age for the overall cohort was 13 (± 1.6) years and the majority were male and injured playing sports. GFAP levels and PCSS scores were significantly higher acutely following mT...

Journal of neurotrauma, Jan 14, 2016

The objectives of the study were to characterize long-term neuropsychological outcomes following ... more The objectives of the study were to characterize long-term neuropsychological outcomes following traumatic brain injury (TBI) sustained during early childhood and determine whether identified neuropsychological impairments mediated the effect of TBI on long-term adaptive functioning. Participants included 16 children with severe TBI, 42 children with moderate TBI, and 72 children with orthopedic injuries (OI) sustained between ages 3 and 7 years. Children completed neuropsychological tests and caregivers completed a structured interview of child adaptive functioning at 6.9 (±1.10) years post injury. Profile analysis and multiple mediator modeling were employed. Children with severe TBI demonstrated poorer fluid reasoning and inhibitory control relative to both children with moderate TBI and OI, as well as slower processing speed relative to the OI group. Both fluid reasoning and processing speed were significant independent mediators of the effect of severe TBI on adaptive functioni...

JAMA Pediatrics, 2016

Pediatric traumatic brain injury (TBI) contributes to impairments in behavior and academic perfor... more Pediatric traumatic brain injury (TBI) contributes to impairments in behavior and academic performance. However, the long-term effects of early childhood TBI on functioning across settings remain poorly understood. To examine the long-term functional outcomes of early childhood TBI relative to early childhood orthopedic injuries (OIs). We also examine the moderating role of the social environment as defined by parent report and observational measures of family functioning, parenting practices, and home environment. A prospective, longitudinal, observational cohort study conducted at each child's home, school, and hospital, including 3 children's hospitals and 1 general hospital in the Midwest. Patients were enrolled in the initial study between January 2003 and October 2006. Follow-ups were completed between January 2010 and April 2015. Fifty-eight children who sustained a TBI (67% of original enrolled cohort) and 72 children who sustained an OI (61% of the original enrolled cohort) were prospectively followed up from shortly after injury (between the ages of 3 and 7 years at enrollment) to an average of 6.7 years after injury, with assessments occurring at multiple points. Long-term functional outcomes in everyday settings, as assessed through the Child and Adolescent Functional Assessment Scale (CAFAS). Of the 130 children included, the median age for those with OIs was 11.72 years and 11.97, 12.21, and 11.72 years for those with complicated mild, moderate, and severe TBIs, respectively. Children with moderate and severe TBI were rated as having more functional impairments in multiple domains than those with OIs (P < .05). Children with complicated mild TBI had greater impairments in school (odds ratio = 2.93; 95% CI = 1.10-7.82) and with thinking (odds ratio = 15.72; 95% CI = 3.31-74.73) than those with OIs. Functional impairments in children with TBI were more pronounced among children from families with higher levels of permissive (mean CAFAS of 49.71, 35.74, 58.14, and 16.16 for severe TBI, moderate TBI, complicated mild TBI, and OI, respectively, with significant difference between severe TBI and OI [difference = 33.55; P < .001] and complicated mild TBI and OI [difference = 41.98; P < .001]) or authoritarian (mean CAFAS of 56.45, 41.80, 54.90, and 17.12 for severe TBI, moderate TBI, complicated mild TBI, and OI, respectively, with significant difference between severe TBI and OI [difference = 39.33; P < .001], moderate TBI and OI [difference = 24.68; P = .003], and complicated mild TBI and OI [difference = 37.78; P < .001]) parenting or with fewer home resources (mean CAFAS of 69.57, 47.45, 49.00, and 23.81 for severe TBI, moderate TBI, complicated mild TBI, and OI, respectively, with significant difference between severe TBI and OI [difference = 45.77; P < .001], moderate TBI and OI [difference = 23.64; P < .001], and complicated mild TBI and OI [difference = 25.20; P < .001]). Even children with relatively mild early TBI experience long-term functional impairments, particularly in the context of less favorable home environments. These findings suggest that improving parenting skills and the quality of the home environment may promote functional recovery following early TBI.

Journal of Urban Health, 2016

We assessed whether economic, legal, and social hardships were associated with human immunodefici... more We assessed whether economic, legal, and social hardships were associated with human immunodeficiency virus (HIV) risk among a sample of Black men who have sex with men (MSM) and whether associations were moderated by city of residence. The study analyzed baseline and follow-up data from HIV Prevention Trials Network 061 (N = 1553). Binary logistic regression assessed associations between hardships and HIV risk indicators. Multivariate regressions were used to test if city of residence had a moderating effect for hardships and HIV risks. Adjusted analyses showed that Black MSM with recent job loss were more likely to engage in condomless insertive anal intercourse (adjusted odds ratios (AOR) = 1.37, 95 % CI 1.01-1.87) and that those with recent financial crisis were more likely to have had two or more male sexual partners in the past 6 months (AOR = 1.65; 95 % CI 1.18-2.29). Black MSM with recent convictions were more likely to have a sexually transmitted infection at 6 months (AOR = 3.97; 95 % CI 1.58-9.94), while those who were unstably housed were more likely to have a sexually transmitted infection at 12 months (AOR = 1.71; 95 %CI 1.02 = 2.86). There were no city of residence and hardship interaction effects on HIV risks. Hardships are important factors that influence HIV risk for Black MSM. Integrating strategies that address structural factors that influence HIV risk may enhance HIV prevention interventions implementation efforts.

American journal of men's health, Jan 12, 2016

Exposure to childhood religious affiliations where the majority of members discourage homosexuali... more Exposure to childhood religious affiliations where the majority of members discourage homosexuality may have negative psychological impacts for Black men who have sex with men. This study tested the hypothesis that exposures to these environments during childhood were associated with adulthood human immunodeficiency virus (HIV)/sexually transmitted infection (STI) behavioral risk and HIV infection, because these exposures influenced HIV/STI risk by undermining race/sexual identity congruence and increasing internalized homophobia and interpersonal anxiety. Structural equation modeling as well as logistic and Poisson regressions were performed using baseline data from HIV Prevention Trials Network 061 (N = 1,553). Childhood religion affiliations that were more discouraging of homosexuality were associated with increased likelihood of HIV infection; however, the association was no longer significant after adjusting for age, income, and education. Having a childhood religion affiliatio...

Journal of Medical Statistics and Informatics, May 27, 2015

Recent work has identified the transition from adolescence to young adulthood as a period with di... more Recent work has identified the transition from adolescence to young adulthood as a period with distinct characteristics that is important for understanding of human development. Self-esteem plays a critical role in this developmental process. We use self-esteem data measured at mean ages 13, 16 and 22, and anxiety disorder diagnosis at mean age of 33 to examine the impact of development of self-esteem on onset of adult anxiety disorder. To analyze these data, we propose a Bayesian joint model with: (1) a linear mixed effects model for the longitudinal measurements, and (2) a generalized linear model for the binary primary endpoint. Our analysis indicates that the mean level of self-esteem, not the change of self-esteem, significantly predicts the onset of adult anxiety disorder. A comparison shows that the joint model yields better predictive accuracy than a two-step model. The respective area under ROC curve (AUC) is 0.60 and 0.75 for the two-step model and the joint model, respectively. The two-step estimate may be biased because this method ignores variability in the individual random effects. We conclude that joint model is the most advantageous model to analyze early life longitudinal data combined with later binary outcome. measurements and event time data. -480. | Article 36. Lin H, Turnbull BW, McCulloch CE and Slate EH. Latent class models for joint analysis of longitudinal biomarker and event process data: application to longitudinal prostate-specific antigen readings and prostate cancer. J Am Stat Assoc. 2002; 96:895-905. | Article of a linear mixed effects model for selfesteem from mean ages 13 to 22 and a generalized linear model for anxiety disorder at mean age 33. J Med Stat Inform. 2015; 3:1. http://dx.

Inquiry : a journal of medical care organization, provision and financing, 2015

Medicare Advantage was implemented in 2004 and the Recovery Audit Contractor (RAC) program was im... more Medicare Advantage was implemented in 2004 and the Recovery Audit Contractor (RAC) program was implemented in Florida during 2005. Both increase surveillance of medical necessity and deny payments for improper admissions. The purpose of the present study was to determine their potential impact on for-profit (FP) and not-for-profit (NFP) hospital operating margins in Florida. FP hospitals were expected to be more adversely affected as admissions growth has been one strategy to improve stock performance, which is not a consideration at NFPs. This study analyzed Florida community hospitals from 2000 through 2010, assessing changes in pre-tax operating margin (PTOM). Florida Agency for Health Care Administration data were analyzed for 104 community hospitals (62 FPs and 42 NFPs). Academic, public, and small hospitals were excluded. A mixed-effects model was used to assess the association of RAC implementation, organizational and payer type variables, and ownership interaction effects on...

Archives of Physical Medicine and Rehabilitation, 2015

Medicare Advantage was implemented in 2004 and the Recovery Audit Contractor (RAC) program was im... more Medicare Advantage was implemented in 2004 and the Recovery Audit Contractor (RAC) program was implemented in Florida during 2005. Both increase surveillance of medical necessity and deny payments for improper admissions. The purpose of the present study was to determine their potential impact on for-profit (FP) and not-for-profit (NFP) hospital operating margins in Florida. FP hospitals were expected to be more adversely affected as admissions growth has been one strategy to improve stock performance, which is not a consideration at NFPs. This study analyzed Florida community hospitals from 2000 through 2010, assessing changes in pre-tax operating margin (PTOM). Florida Agency for Health Care Administration data were analyzed for 104 community hospitals (62 FPs and 42 NFPs). Academic, public, and small hospitals were excluded. A mixed-effects model was used to assess the association of RAC implementation, organizational and payer type variables, and ownership interaction effects on PTOM. FP hospitals began the period with a higher average PTOM, but converged with NFPs during the study period. The average Medicare Advantage effect was not significant for either ownership type. The magnitude of the RAC variable was significantly negative for average PTOM at FPs (−4.68) and positive at NFPs (0.08), meaning RAC was associated with decreasing PTOM at FP hospitals only. RAC complements other Medicare surveillance systems that detect medically unnecessary admissions, coding errors, fraud, and abuse. Since its implementation in Florida, average FP and NFP operating margins have been similar, such that the higher margins reported for FP hospitals in the 1990s are no longer evident.

The Journal of head trauma rehabilitation, Jan 24, 2015

To elucidate the association of a functional catechol-O-methyltransferase (COMT) genotype (rs4680... more To elucidate the association of a functional catechol-O-methyltransferase (COMT) genotype (rs4680) with recovery of executive functions up to 18 months after early childhood traumatic brain injury (TBI) compared with an orthopedic injury (OI) group. Outpatient. A total of 134 children with a moderate to severe TBI (n = 63) or OI (n = 71) between the ages of 3 and 6 years who were followed 18 months postinjury. Case-comparison, longitudinal cohort MAIN MEASURES:: The Behavior Rating Inventory of Executive Function, developmental NEuroPSYchological Assessment (NEPSY) of Verbal Fluency, and a modified Stroop Test for young children (Shape School). The low-activity COMT enzyme genotype (AA) was associated with better scores on the developmental NEPSY of Verbal Fluency (F = 3.80; P = .02) and the Shape School (F = 2.89; P = .06) in all participants when controlling for injury type (TBI vs OI) over the first 18 months after injury. Injury type (TBI vs OI) did not significantly moderate th...

Research in Nursing & Health, 2015

Ghanaian men who have sex with men (MSM) have a high HIV seroprevalence, but despite a critical n... more Ghanaian men who have sex with men (MSM) have a high HIV seroprevalence, but despite a critical need to address this public health concern, research evidence has been extremely limited on influences on sexual risk behavior among MSM in Ghana. To investigate associations between HIV/STD knowledge, HIV stigma, and sexual behaviors in a sample of MSM in Ghana, we conducted a secondary data analysis of cross-sectional survey data from a non-probability sample of Ghanaian MSM (N ¼ 137). Nearly all the men (93%) had more than one current sex partner (M ¼ 5.11, SD ¼ 7.4). Of those reported partners, the average number of current female sexual partners was 1.1 (SD ¼ 2.6). Overall, knowledge levels about HIV and STDs were low, and HIV stigma was high. There was no agerelated difference in HIV stigma. Younger MSM ( 25 years) used condoms less often for anal and vaginal sex than did those over 25. Relative frequency of condom use for oral sex was lower in younger men who had higher STD knowledge and also was lower in older men who reported high HIV stigma. Knowledge and stigma were not associated with condom use for anal or vaginal sex in either age group. These descriptive data highlight the need for the development of intervention programs that address HIV/STD prevention knowledge gaps and reduce HIV stigma in Ghanaian communities. Intervention research in Ghana should address age-groupspecific HIV prevention needs of MSM youth. ß

Biometrics, 2014

There has been an increasing interest in the analysis of spatially distributed multivariate binar... more There has been an increasing interest in the analysis of spatially distributed multivariate binary data motivated by a wide range of research problems. Two types of correlations are usually involved: the correlation between the multiple outcomes at one location and the spatial correlation between the locations for one particular outcome. The commonly used regression models only consider one type of correlations while ignoring or modeling inappropriately the other one. To address this limitation, we adopt a Bayesian nonparametric approach to jointly modeling multivariate spatial binary data by integrating both types of correlations. A multivariate probit model is employed to link the binary outcomes to Gaussian latent variables; and Gaussian processes are applied to specify the spatially correlated random effects. We develop an efficient Markov chain Monte Carlo algorithm for the posterior computation. We illustrate the proposed model on simulation studies and a multidrug-resistant t...

In this study, we employed an eigenfunction decomposition algorithm associated with a Moran's coe... more In this study, we employed an eigenfunction decomposition algorithm associated with a Moran's coefficient to investigate district-level non-linearity in an empirical dataset of spatiotemporal-sampled MDR-TB parameter estimators sampled in San Juan de Lurigancho (SJL) Lima, Peru. The nonparametric technique attempted to remove the inherent autocorrelation in the model by introducing appropriate synthetic surrogate variants. We also constructed a robust Bayesian Poisson model to generate unbiased estimators for qualitatively assessing resistance to four commonly used drugs in TB treatment: isoniazid, rifampin, ethambutol, and streptomycin. Initially, data of residential addresses of individual patients with smear-positive MDR-TB were geocoded in ArcGIS. Next, the sampled data were matched automatically and interactively within the geodatabase. The MDR-TB data feature attributes were then calculated and digitally overlaid onto sub-meter resolution satellite data within a 1 km buffer of 31 georeferenced health centers using a 10 m 2 grid-based algorithm. Global autocorrelation statistics were then generated by decomposing the sampled data into positive and negative spatial filter eigenvectors using the eigenfunction decomposition algorithm. Bayesian Poisson projections were then rendered employing normal priors for each of the sampled estimators. A Residual Moran's coefficient (MC) minimization criterion was then applied to the clinical coefficients generated from the decomposition algorithm to detect any unaccounted latent autocorrelation error in the estimators. The model accounted for approximately 14% pseudo-replicated information and exhibited positive residual autocorrelation. Spatial statistics can elucidate the mechanics of MDR-TB transmission by prioritizing clinical covariates for identifying spatial distribution of high-risk populations and random heterogeneity in resistant strains.