Using an empirical binomial hierarchical Bayesian model as an alternative to analyzing data from multisite studies

This article explores the statistical methodologies used in demonstration and effectiveness studies when the treatments are applied across multiple settings. The importance of evaluating and how to evaluate these types of studies are discussed. As an alternative to standard methodology, the authors of this article offer an empirical binomial hierarchical Bayesian model as a way to effectively evaluate multisite studies. An application of using the Bayesian model in a real-world multisite study is given.     

SOME DEMOGRAPHIC CORRELATES OF HIV/AIDS-RELATED DISCRIMINATION

In late 1991, a survey was made of HIV/AIDS-related discrimination in the Australian community. Structured telephone interviews were conducted with a random sample of 2,053 respondents. Twenty-one questions provided an index of expressed discrimination. Social contact with HIV-positive people was a significant predictor of low levels of discrimination. Other important predictors of (lower) levels of discrimination were: social contact with gay men, education, sex, age, sexual identity, and sexual experience. Social contact with gay men was the single best predictor of positive attitudes towards people with HIV/AIDS.     

Gay Men's Knowledge of HIV Transmission and ‘Safe’ Sex: A Question of Accuracy

The study described in this paper is part of a project assessing the impact of the HIV epidemic on 535 men who have sex with men. These men were surveyed about their knowledge of HIV, their sexual practices, other issues concerning the transmission of HIV, and AIDS. This paper focuses on these men's beliefs about HIV transmission, their perceptions of the safety of a number of sexual and social practices, and the factors influencing these perceptions. The findings indicate, in general, that the men surveyed were moderately well informed about HIV transmission. Some twenty percent of the men were well-informed about both ‘safe’ and ‘unsafe’ sexual practices, a small number were ill-informed and the remainder, the majority, were well-informed about some aspects and ill-informed about others. The data suggest that information from the mainstream and gay press is not only differentially available but that information is processed and interpreted by the men in different ways. Variables which influence the manner in which information is interpreted are place of residence (locale), awareness of gay community posters and pamphlets, and the men's sexual practice; these are associated with cautiousness or rashness in the men's judgments of safety and risk.