Optimal Hypothesis Testing: From Semi to Fully Bayes Factors.

We propose and examine statistical test-strategies that are somewhat between the maximum likelihood ratio and Bayes factor methods that are well addressed in the literature. The paper shows an optimality of the proposed tests of hypothesis. We demonstrate that our approach can be easily applied to practical studies, because execution of the tests does not require deriving of asymptotical analytical solutions regarding the type I error.

Estimation of Variance Components in the Mixed-Effects Models: A Comparison Between Analysis of Variance and Spectral Decomposition.

The mixed-effects models with two variance components are often used to analyze longitudinal data. For these models, we compare two approaches to estimating the variance components, the analysis of variance approach and the spectral decomposition approach. We establish a necessary and sufficient condition for the two approaches to yield identical estimates, and some sufficient conditions for the superiority of one approach over the other, under the mean squared error criterion.

Race of male sex partners and occurrence of bacterial vaginosis.

Background: Whether bacterial vaginosis (BV) is sexually transmitted is uncertain. Also it is unknown why BV is approximately twice as prevalent among black as among white women. An association of BV with a characteristic of the male sex partner, such as race, might support sexual transmission as well as account for the observed ethnic disparity in BV.

Personal hygienic behaviors and bacterial vaginosis.

Background: Vaginal douching is consistently associated with bacterial vaginosis (BV), but whether it is a cause or result of BV remains unknown. The association between BV and other feminine hygienic behaviors is less studied; if BV symptoms caused behavior change then all hygiene behaviors might be more common among women with BV. Lack of association between nondouching hygiene behavior and BV would argue against reverse causation.

Dietary intake of selected nutrients affects bacterial vaginosis in women.

Bacterial vaginosis (BV), a condition of altered vaginal flora, is associated with various adverse reproductive health outcomes. We evaluated the association between diet and the presence of BV in a subset of 1521 women (86% African-American) from a larger study of vaginal flora. Participants completed the Block Food Questionnaire and clinical assessments and self-report measures of sexual and hygiene behavior.

A pilot study of vaginal flora changes with randomization to cessation of douching.

Objectives: The objectives of this study were to determine whether women who douche regularly would enter a randomized trial of douching cessation or continuation, whether they would adhere to the assigned behavior, and whether there was a dramatic impact on vaginal flora.

Goal: The goal of this study was to determine the feasibility of a large, definitive trial of douching cessation.

Study Design: Women who douched at least weekly and who had either bacterial vaginosis or normal flora by Gram stain were assigned at random either to continue douching or to stop for 8 weeks.

The association of psychosocial stress and bacterial vaginosis in a longitudinal cohort.

Objective: The purpose of this study was to assess the association of psychosocial stress with bacterial vaginosis in a longitudinal sample of nonpregnant women.

Study Design: A 1-year prospective longitudinal design was used. Nonpregnant women (n = 3614) aged 15 to 44 years were recruited at routine health care visits.

Vulvovaginal symptoms in women with bacterial vaginosis.

Objective: A substantial, but highly variable, percentage of women with bacterial vaginosis are said to be asymptomatic. The purpose of this study was to estimate the prevalence of symptoms among women with bacterial vaginosis compared with women without bacterial vaginosis by direct, explicit, and detailed questioning of these women.

Methods: Women presenting for a routine health care visit at 12 health department clinics in Birmingham, Alabama, were recruited to participate in a longitudinal study of vaginal flora.

Regression models for unbalanced longitudinal ordinal data: computer software and a simulation study.

A computer program GGOREX in the form of a SAS macro is developed for the analysis of longitudinal ordinal data. It is extended from GEECAT and GEEGOR developed by Williamson, Lipsitz and Kim in their paper in 1999. An illustrative example with some preliminary data from a study conducted by the National Institute of Child Health and Human Development and the University of Alabama at Birmingham is given.