Systematic review of statistical methods for safety data in malaria chemoprevention in pregnancy trials.

Background: Drug safety assessments in clinical trials present unique analytical challenges. Some of these include adjusting for individual follow-up time, repeated measurements of multiple outcomes and missing data among others. Furthermore, pre-specifying appropriate analysis becomes difficult as some safety endpoints are unexpected.

Systematic review of analytical methods applied to longitudinal studies of malaria.

Background: Modelling risk of malaria in longitudinal studies is common, because individuals are at risk for repeated infections over time. Malaria infections result in acquired immunity to clinical malaria disease. Prospective cohorts are an ideal design to relate the historical exposure to infection and development of clinical malaria over time, and analysis methods should consider the longitudinal nature of the data.

Psychosocial correlates of alcohol and other substance use among low-income adolescents in peri-urban Johannesburg, South Africa: A focus on gender differences.

Alcohol and other drug use is prevalent among peri-urban, South African adolescents. We identified correlates of alcohol and other drug use by gender among adolescents (age = 16-18 years; N = 822) in peri-urban Johannesburg. Interviewer-administered surveys assessed sexual activity, alcohol and other drug use, and relevant psychosocial factors.

Exposure to and experiences of violence among adolescents in lower socio-economic groups in Johannesburg, South Africa.

Background: We explored exposure to and experiences of violence and their risk factors amongst ethnically diverse adolescents from lower socio economic groups in Johannesburg.

Methods: This cross-sectional study recruited a stratified sample of 16-18 year old adolescents from four low socio-economic suburbs in Johannesburg to reflect ethnic group clustering. We collected socio-demographic, sexual behaviour, alcohol and drug use and trauma events data.

Factors associated with mortality in HIV-infected people in rural and urban South Africa.

Background: Factors associated with mortality in HIV-infected people in sub-Saharan Africa are widely reported. However rural-urban disparities and their association with all-cause mortality remain unclear. Furthermore, commonly used classical Cox regression ignores unmeasured variables and frailty.

Correlates of sexual risk among sexual minority and heterosexual South African youths.

We explored psychosocial correlates of sexual risk among heterosexual and sexual minority youths (SMYs) in Johannesburg, South Africa. Young people 16 to 18 years old (n = 822) were administered surveys assessing demographic characteristics, sexual behaviors, mental health, and parent-child communication. Adjusted multivariate regressions examining correlates of sexual risk revealed that SMYs had more sexual partners than heterosexual youths (B = 3.

A review of the study designs and statistical methods used in the determination of predictors of all-cause mortality in HIV-infected cohorts: 2002-2011.

Background: Research in the predictors of all-cause mortality in HIV-infected people has widely been reported in literature. Making an informed decision requires understanding the methods used.

Objectives: We present a review on study designs, statistical methods and their appropriateness in original articles reporting on predictors of all-cause mortality in HIV-infected people between January 2002 and December 2011.

The effect of a maturing antiretroviral program on early mortality for patients with advanced immune-suppression in Soweto, South Africa.

Objective: We hypothesize that time to initiate care and maturity of a treatment program impact on outcome of severely immuno-compromised patients with higher risk of mortality.

Design: We conducted a retrospective cohort analysis at the Perinatal HIV Research Unit Adult ART clinic, Soweto, South Africa.

Methods: ELIGIBILITY CRITERIA FOR THIS ANALYSIS WERE: attendance for minimum one visit between August 2004 and August 2010, age >18 years, CD4 count < 50 cells/mm(3) and ART-naïve at screening.

Factors associated with not testing for HIV and consistent condom use among men in Soweto, South Africa.

Background: Besides access to medical male circumcision, HIV testing, access to condoms and consistent condom use are additional strategies men can use to prevent HIV acquisition. We examine male behavior toward testing and condom use.

Objective: To determine factors associated with never testing for HIV and consistent condom use among men who never test in Soweto.

Willingness to participate in biomedical HIV prevention studies after the HVTN 503/Phambili trial: a survey conducted among adolescents in Soweto, South Africa.

Objectives: Adolescents may be appropriate for inclusion in biomedical HIV prevention trials. Adolescents' overall willingness to participate (WTP) in biomedical HIV prevention trials was examined, including after the prematurely discontinued phase IIb HVTN 503/Phambili HIV vaccine trial, in Soweto, South Africa.

Methods: An interview-administered cross-sectional survey was conducted among 506 adolescents (16-18 years) between October 2008 and March 2009.

Improving national data collection systems from voluntary counselling and testing centres in Kenya.

Problem: Voluntary counselling and testing (VCT) data from the registered sites in Kenya have been fraught with challenges, leading to insufficient statistics in the national office for planning purposes. An exercise was carried out to determine the barriers to the flow of data in VCT sites in Kenya.

Approach: A record-based survey was conducted at 332 VCT sites in Kenya.