Vital and Health Statistics Commons^™

Calcium Supplemental Usage And Potential Health Issues Sssociated With The Rate Of Usage In Las Vegas, Nv, Tanesha Nicole Moss

UNLV Theses, Dissertations, Professional Papers, and Capstones

Calcium is a very important nutrient and as such, it is very important that all humans consume sufficient amounts. However, some calcium supplements have been known to contain small quantities of lead. This research project used a retrospective approach to explore the trade-off between the benefits of calcium vs. the potential lead exposure amongst people who are taking these supplements. A survey consisting of 10 questions was used to try to assess the rate of consumption of specific types of calcium supplements. This research project obtained lead levels in calcium supplements from previous research and applied that data into this …

Causal Inference For Continuous-Time Processes When Covariates Are Observed Only At Discrete Times, Mingyuan Zhang, Marshall M. Joffe, Dylan S. Small

Statistics Papers

Most of the work on the structural nested model and g-estimation for causal inference in longitudinal data assumes a discrete-time underlying data generating process. However, in some observational studies, it is more reasonable to assume that the data are generated from a continuous-time process and are only observable at discrete time points. When these circumstances arise, the sequential randomization assumption in the observed discrete-time data, which is essential in justifying discrete-time g-estimation, may not be reasonable. Under a deterministic model, we discuss other useful assumptions that guarantee the consistency of discrete-time g-estimation. In more general cases, when those assumptions are …

Retracing Micro-Epidemics Of Chagas Disease Using Epicenter Regression, Michael Z. Levy, Dylan S. Small, Daril A. Vilhena, Natalie M. Bowman, Vivian Kawai, Juan G. Cornejo Del Carpio, Eleazar Cordova-Benzaquen, Robert H. Gilman, Caryn Bern, Joshua B. Plotkin

Statistics Papers

Vector-borne transmission of Chagas disease has become an urban problem in the city of Arequipa, Peru, yet the debilitating symptoms that can occur in the chronic stage of the disease are rarely seen in hospitals in the city. The lack of obvious clinical disease in Arequipa has led to speculation that the local strain of the etiologic agent, Trypanosoma cruzi, has low chronic pathogenicity. The long asymptomatic period of Chagas disease leads us to an alternative hypothesis for the absence of clinical cases in Arequipa: transmission in the city may be so recent that most infected individuals have yet …

Using Split Samples And Evidence Factors In An Observational Study Of Neonatal Outcomes, Kai Zhang, Dylan S. Small, Scott A. Lorch, Sindhu K. Srinivas, Paul R. Rosenbaum

Statistics Papers

During a few years around the turn of the millennium, a series of local hospitals in Philadelphia closed their obstetrics units, with the consequence that many mothers-to-be arrived unexpectedly at the city’s large, regional teaching hospitals whose obstetrics units remained open. Nothing comparable happened in other United States cities, where there were only sporadic changes in the availability of obstetrics units. What effect did these closures have on mothers and their newborns? We study this question by comparing Philadelphia before and after the closures to a control Philadelphia constructed from elsewhere in Pennsylvania, California, and Missouri, matching mothers for 59 …

Academic Predictors Of National Council Licensure Examination For Registered Nurses Pass Rates, Maybeth J. Elliott

Walden Dissertations and Doctoral Studies

The United States continues to be affected by a severe, long-standing nursing shortage that is not projected to resolve within the next 10 or more years. Unsuccessful passage of the National Council Licensure Examination for Registered Nurses (NCLEX-RN) among graduate nurses remains one of several key contributors to the nursing shortage. The goal of this study was to identify if either cumulative fall semester GPA; the overall prenursing science, mathematics, and English GPA; type of high school background; TOEFL score; clinical pass or fail; and on-time program completion best predicted passage of NCLEX-RN. Archived records from the academic years of …

The Determinants Of Colorectal Cancer Survival Disparities In Nevada, Lucas N. Wassira

UNLV Theses, Dissertations, Professional Papers, and Capstones

Different population groups across Nevada and throughout the United States suffer disproportionately from colorectal cancer and its after-effects. Overcoming cancer health disparities is important for lessening the burden of cancer. There has been an overall decline in the incidence of and mortality from colorectal cancer (CRC). This is likely due, in part, to the increasing use of screening procedures such as Fecal Occult Blood Test (FOBT) and/or endoscopy, which can reduce the risk of CRC mortality by fifty percent. Nevertheless, screening procedures are routinely used by only fifty percent of Americans aged fifty years and older. Despite overall mortality decreasing …

Culturally-Adapted And Audio-Technology Assisted Hiv/Aids Awareness And Education Program In Rural Nigeria: A Cohort Study, Ighovwerha Ofotokun, Jose Nilo G. Binongo, Eli S. Rosenberg, Michael Kane, Rick Ifland, Jeffrey L. Lennox, Kirk A. Easley

Faculty Publications

Background: HIV-awareness programs tailored toward the needs of rural communities are needed. We sought to quantify change in HIV knowledge in three rural Nigerian villages following an integrated culturally adapted and technology assisted educational intervention.

Methods: A prospective 14-week cohort study was designed to compare short-term changes in HIV knowledge between seminar-based education program and a novel program, which capitalized on the rural culture of small-group oral learning and was delivered by portable digital-audio technology.

Results: Participants were mostly Moslem (99%), male (53.5%), with no formal education (55%). Baseline HIV knowledge was low (< 80% correct answers for 9 of the 10 questions). Knowledge gain was higher (p < 0.0001 for 8 of 10 questions) in the integrated culturally adapted and technology-facilitated (n = 511) compared with the seminar-based (n = 474) program.

Conclusions: Baseline HIV-awareness was low. Culturally …

Hidden Markov Models For Alcoholism Treatment Trial Data, Kenneth E. Shirley, Dylan S. Small, Kevin G. Lynch, Stephen A. Maisto, David W. Oslin

Statistics Papers

In a clinical trial of a treatment for alcoholism, a common response variable of interest is the number of alcoholic drinks consumed by each subject each day, or an ordinal version of this response, with levels corresponding to abstinence, light drinking and heavy drinking. In these trials, within-subject drinking patterns are often characterized by alternating periods of heavy drinking and abstinence. For this reason, many statistical models for time series that assume steady behavior over time and white noise errors do not fit alcohol data well. In this paper we propose to describe subjects’ drinking behavior using Markov models and …