Public Health

The structure and systems of state health departments (SHD) may affect reporting of foodborne disease outbreak (FBDO) hospitalizations. Evaluation of SHD by investigating the contributions of structural capacity elements (SCE) will provide an accurate measure of performance and highlight areas for development of effective strategies for improvement. This study investigated the relationship between organizational and structural characteristics of SHD and systems for FBDO reporting, and included three manuscripts designed to address seven hypotheses, as well as a conclusion chapter interpreting the findings as they relate to the overall research question. Study findings identified consistently higher reports of hospitalization due to foodborne illness from third party payers compared to SHDs between 2006 and 2009 in 30 of the 31 states analyzed. Furthermore, significantly different rates of reporting among states with mixed governance classification were seen when compared to those with centralized and decentralized governance; associations between total laboratory expenditures and total food-related hospitalizations reported were also identified when analyzing healthcare claims data. This dissertation contributes to the current knowledge base for public health services and systems research, as well as food safety surveillance and reporting, and provides an innovative approach to using secondary databases to investigate food safety issues. Findings support the conclusion that collaboration between public and private agencies would support improvements in data collection and foodborne illness surveillance.

Temple University – Theses

Public Health

The use of mobile communication devices (MCDs) by drivers is a significant public health problem. Research suggests that MCD use plays a role in almost 400,000 traffic crashes each year, resulting in over 3,000 deaths (NHTSA, 2013). Drivers using an MCD are as much as four times more likely to crash as other motorists (Redelmeier & Tibshirani, 1997). Since 2001 forty-eight states have adopted one or more laws aimed at reducing the use of MCDs by drivers, many of which have been strengthened through subsequent amendments. Evaluations have yielded a mixed picture of their effectiveness (Braitman & McCartt, 2010; Highway Loss Data Institute, 2010; McCartt & Geary, 2004; McCartt, Hellinga, Strouse, & Farmer, 2010). Existing studies, however, have been limited by various design features. This study employs time-series methods to explore whether laws prohibiting use of MCDs by young drivers effectively reduce crash fatalities. The quasi-experimental design relies on an identification strategy that is common in empirical legal studies but has not yet been applied to laws regulating driver MCD use. The implementation of the identification strategy leverages the developing concept of legal epidemiology. Four state laws are ultimately evaluated. The primary analytic approach is difference-in-difference. In two of the four instances, there is some evidence suggesting a protective effect could be attributed to the law. However, this evidence was limited and differed in relation to specification choices. These findings cast doubt on some fifty state panel analyses that have suggested that laws are effectively decreasing MCD use and associated harms.

Temple University – Theses

Public Health

Background: Physicians do not always provide appropriate patient care, due in part to inadequacy in their education and training. Performance outcomes, such as individuals' examination scores have been linked to future performance as physicians, accentuating the need for high-quality educational institutions. While the medical school accreditation process in the United States assures a uniform standard of quality, approximately one quarter of physicians in training and in practice in the United States graduated from medical schools located outside of the United States or Canada. These graduates of international medical schools (IMGs) have been more likely than domestically educated doctors to practice primary care and treat underserved and minority populations. An increasing proportion of IMGs who seek to enter post-graduate training programs and subsequent licensure in the United States graduated from medical schools located in the Caribbean. The quality of medical education at some of these schools has been questioned. Accreditation systems are frequently viewed as a way to ensure the quality of medical education, although currently there is limited data linking an educational oversight mechanism to better performance of the graduates. In addition, accreditation systems vary in the methodology, standards, and procedures used to evaluate educational programs. The purpose of the first phase of the present research was to examine medical education accreditation practices around the world, with special focus on the Caribbean region, to determine the association of accreditation of medical schools with student/graduate performance on examinations. The aim of the second phase of this research was to evaluate the quality of a select group of accrediting agencies and the association of quality with student/graduate outcomes. Methods All IMGs seeking to enter graduate training positions in the United States must first be certified by the Educational Commission for Foreign Medical Graduates (ECFMG). In addition to other requirements, ECFMG certification includes passing scores on the United States Medical Licensing Examination (USMLE) Step 1 (basic science), Step 2 Clinical Knowledge (CK), and Step 2 Clinical Skills (CS). In the first phase, all IMGs taking one or more examinations leading to ECFMG certification during the five-year study period (January 1, 2006 through December 31, 2010), and who graduated from, or attended at the time of testing, a school located in a country that met the accreditation inclusion criteria, were included in the study population. First-attempt pass rates for each examination were calculated based on personal variables (gender, years elapsed since graduation at the time the individual took an examination [<3 years versus ≥ years], native language [English versus all others]), and on accreditation status of an individual's medical school. Next, separately for each examination, a generalized estimating equations model was used to investigate the effect of accreditation after…

Public Health

Background: Air pollution has been associated with adverse health effects for all-cause and specific respiratory morbidity and mortality outcomes. Acute exacerbations of COPD (AE-COPD) accelerate the decline in pulmonary function and are associated with greater mortality, morbidity, health care utilization, and reduced quality of life. Since the 1970 Clean Air Act was implemented, important reductions in air pollution have been achieved, but no safe threshold has been identified. Objectives: The study was planned to evaluate associations between exposure to ambient concentrations of five criteria air pollutants (CO, SO2/, NO2/, ozone, PM2.5/) in Philadelphia, Pennsylvania, and visits to Temple University Hospital for AE-COPD, from January 1, 2005 through March 31, 2007. To identify subgroups with greater susceptibility to air pollution, associations were examined according to age, gender, race, residence, and antibiotic prescription. Methods: Average daily air pollutant concentrations were obtained from the EPA's Air Quality Services Data Mart. Air pollutant exposures were evaluated for the day of the visit (lag0), one and two days preceding the visit (lag1 and lag2), and the average concentration over three days (lag012). Poisson regression provided rate ratios (RRs) to estimate associations between air pollution exposures and AE-COPD hospital visits. Results: Of 1546 hospital visits for AE-COPD, 43% were from persons 65 years or older, 50% of each gender, and 90% from Philadelphia. In single pollutant models, increased RRs were present at all lags for NO2/ (e.g., RR = 2.27 [95%CI: 1.52, 3.38] at lag012) and SO2/ (e.g., RR = 1.70 [95%CI: 1.38, 2.08] at lag012). For PM2.5/, the direct effect was present only during the winter at lag1, lag2, and lag012 (RR = 1.79 [95%CI: 1.08, 2.96]). Inverse associations were present for ozone at all lags (e.g., RR = 0.64 [95%CI: 0.53, 0.76] at lag012). Compared to the cohort as a whole, those ≥ 65 years of age were at greater risk of an AE-COPD hospital visit associated with PM2.5/ and CO at lag012, with NO2/ and SO2/ at lag0 and lag012, but there was no difference in ozone effect. Conclusions: Primary gaseous air pollution exposures (SO2/, CO, NO2/) were associated with increased AE-COPD hospital visits among COPD patients at Temple University Hospital. The effects of SO2/, CO, NO2/, and PM2.5 were greater for the subgroup ≥ 65 years of age compared to the cohort as a whole. Inverse associations with ozone were consistent across subgroups. These results suggest that air quality during the study period was insufficient to protect the health of COPD patients, especially those ≥ 65 years old. Further study is needed to understand generalizability to other populations and to evaluate lower ranges of exposure from current levels of air pollution.

Temple University – Theses

Kinesiology

Purpose: Evidence has accumulated to show that blood pressure variability (BPV) has a striking relationship with cardiovascular (CV) risk. Despite the mounting evidence implicating BPV as a CV risk factor, scant attention has been paid to: (1) the mechanisms by which high BPV confers greater CV risk; and (2) the efficacy of non-pharmacologic treatment modalities in the attenuation of BPV. In order to address these two unresolved questions, the purpose of this dissertation was twofold. The purpose of study1 was to investigate the association between measures of short-term BPV (24-hour BPV) and long-term BPV (visit-to-visit BPV) with markers of endothelial health in a cohort of African Americans in order to determine if increased BPV may confer greater CV risk by eliciting injury to the endothelium. The purpose of study #2 was to investigate the effects of a 6-month aerobic exercise training (AEXT) intervention on visit-to-visit BPV and 24-hour BPV in the same cohort of African Americans in order to provide the first available data on the efficacy of a non-pharmacologic treatment modality in the lowering of BPV. Methods: We recruited 72 African Americans who were sedentary, non-diabetic, non-smoking, and free of CV and renal disease. Before and after a 6-month AEXT intervention, office blood pressure (BP) was measured at 3 separate visits and 24-hour ambulatory BP monitoring (ABPM) was conducted to measure visit-to-visit BPV and 24-hour BPV, respectively. Right brachial artery diameter was assessed at rest, during flow-mediated dilation (FMD), and after nitroglycerin-mediated dilation (NMD). Peak and area under the curve (AUC) were calculated as measures of FMD and NMD, and the FMD/NMD ratio was calculated as a measure of endothelial function normalized by smooth muscle function. Fasted blood samples were obtained and were analyzed for circulating EMPs expressed as CD31+CD42- and CD62E+ EMPs. Results: In study #1, participants with higher 24-hour diastolic BPV (DBPV) had significantly lower CD31+CD42- EMPs compared to participants with lower 24-hour DBPV. When categorized according to visit-to-visit DBPV, participants with higher visit-to-visit DBPV had a significantly lower FMD/NMD ratio, and significantly higher %NMDpeak and NMDAUCs compared to participants with lower visit-to-visit DBPV. When analyzed as continuous variables, 24-hour mean arterial pressure variability (MAPV) was inversely associated with CD31+CD42- EMPs visit-to-visit DBPV was inversely associated with the FMD/NMD ratio and positively associated with %NMDpeak and NMDAUC; and 24-hour DBPV was positively associated with NMDAUC. All associations were independent of age, gender, BMI, mean BP, and pulse pressure. In study #2 investigating the effects of AEXT in 33 participants who completed the study, 24-hour DBPV and 24-hour MAPV were significantly increased after AEXT. The increase in 24-hour DBPV was independent of changes in BMI, mean BP, and self-reported sleep time. Heart rate variability (HRV) derived from ABPM was associated with…

Kinesiology

Purpose: Clinical, epidemiological and basic research evidence supports the inclusion of regular physical activity as a tool for the prevention of chronic disease and the enhancement of overall health. Cardiovascular disease (CVD), the number one cause of death in the United States, is more prevalent in African Americans when compared to other races. Extensive data suggests that increasing physical activity level, particularly with aerobic exercise training (AEXT), can improve modifiable risk factors (hypertension, obesity, dyslipidemia) for CVD. The common pathology for cardiovascular (CV) risk factors is atherosclerosis. Central to the complex pathology of atherosclerosis is the vascular endothelium. In recent years, autocrine and paracrine endothelial biomarkers that directly affect endothelial status (activated vs. inactivated) have been implicated in the pathogenesis of the development and progression of CVD and its precursors. Exercise interventions have been used to modify the concentrations of endothelial biomarkers in populations with varying disease states. The purpose of this study was to identify plasma and urinary biomarkers that are associated with aerobic capacity (VO2max) in a sedentary African American population and further determine the effect of 6-months of AEXT on the concentration and activity of the biomarkers. Methods: Participants were recruited from the Philadelphia, PA area. Twenty two pre-hypertensive African Americans (SBP 122.15±10.33, DBP 77.00±5.88; 52.27±6.25 years of age) were included. Routine fasting blood samples were drawn to assess blood lipids and fasting blood glucose along with urinalysis to rule out kidney dysfunction or disease. Subjects had a physical examination and BP measured under standardized conditions. Exclusion criteria included smoking, a body mass index (BMI) > 40 kg/m2, alcohol intake of more than 3 drinks per day, diabetes (fasting glucose level >126 mg/dl), total cholesterol >240 mg/dl, renal or CV disease. On a separate day, a sub-maximal graded exercise test with gas analysis was conducted to determine aerobic capacity. VO2max was estimated from the baseline submaximal graded exercise test. Regression analysis was used to calculate VO2max. Participants underwent 6 months of AEXT at a prescribed 3 sessions per week for 40 minutes at 65% VO2max. Plasma biomarkers of oxidative stress (8-isoprostane PGF2a), cellular activation (VCAM-1), anti-oxidants (SOD), vascular tone (NO) and anti-thrombosis (2,3 dinor 6-keto Prostaglandin F1a) were measured before and after AEXT by commercially available EIA and ELISA kits. CRP, a biomarker of systemic inflammation and predictor of CV events was assessed. Results: Estimated VO2max values confirmed that the exercise group was untrained (VO2max: 25.31 ± 3.91 ml/kg/min). At baseline the most significant correlations observed were between VO2max and CRP (r= -.50, p= .01) as well as CRP and 8-isoprostane PGF2a (r= .88, p2max and CRP remained statistically significant (r= -.46, p= .02). Nitric oxide and VCAM-1…

Public Health

Despite the decline in homicide rates over the last twenty years, youth violence remains a significant public health issue which disproportionately affects young people of color and is often found at higher rates in urban, disadvantaged neighborhoods. To advance prevention efforts it is important to consider factors beyond the individual such as neighborhood and societal factors that influence youth development. Furthermore, input on neighborhood level factors from members of communities that experience high rates of youth violence can provide unique insight into community life and culture as well as engage communities in prevention efforts. The purpose of this project was to demonstrate a measurement development process that includes community participation and through that process, establish a measure that captures neighborhood social processes that may influence youth behavior as a local urban, disadvantaged community has described them. Previous community based participatory research (CBPR) efforts have identified a concept "neighborhood youth support" as important to youth violence prevention. Guided by principles of CBPR, the current study employed a mixed methods design to develop a measure of this concept. Results of a comprehensive review of social support concepts were used to identify constructs, measures and quality of the measures for the purpose of operationalizing "neighborhood youth support". Next a draft instrument and instructions for the instrument were created. This instrument was then assessed for content validity using a participatory research approach that engaged a community expert panel to review, revise and approve the final instrument for testing in the community. The measure was piloted with a convenience sample of community residents (N=65) and subsequently analyzed for internal consistency reliability and construct validity. Eleven community members and three academic researchers participated on the panel. The final measure consisted of 25 questions in five sub-scales: leadership, respect, intervening in negative behavior, adult presence, and active engagement in positive behavior. Results showed the individual scales to be internally consistent (alpha .626-.783). Principal axis factoring concluded that three of the five scales were measuring one domain while two others were not as clear. Spearman correlations showed moderate to strong positive correlations between these scales and already established scales thought to work similarly as the new scales. Results showed that the measure had good internal consistency and behaved as predicted in comparison to previously validated measures. Moreover, it was established that partnering with community members in measurement development is feasible. This study will help to inform future participatory projects by providing community and academic partnerships with a process for including community voice in measurement development. Finally, the results of this study could help future prevention efforts by providing academic and…