Van Der Straten A.,University of California at San Francisco |
Van Damme L.,FHI 360 |
Haberer J.E.,Massachusetts General Hospital |
Bangsberg D.R.,Harvard University
AIDS | Year: 2012
Although the balance of recent evidence supports the efficacy of antiretroviral (ARV)-based pre-exposure prophylaxis (PrEP) against HIV-1 infection, recent negative trial results are perplexing. Of seven trials with available HIV endpoints, three different products have been tested: tenofovir 1% vaginal gel, oral tenofovir disoproxil fumarate (TDF) tablets, and TDF/emtricitabine tablets. Six of these trials were conducted exclusively in sub-Saharan Africa; all found the products to be well tolerated, and four demonstrated effectiveness. Furthermore, the HIV Prevention Trial Network (HPTN) 052 trial recently confirmed that antiretroviral treatment leads to 96% reduction in transmission to HIV-negative partners in HIV-serodiscordant couples. These results, along with human and animal data, provide substantial evidence for the efficacy of antiretroviral-based HIV prevention. Yet assessment of oral TDF/emtricitabine in the FEM-PrEP study and of oral and vaginal tenofovir in the Microbicide Trial Network (MTN)-003 trial (VOICE) was stopped for futility. How do we make sense of these discrepant results? We believe that adherence is a key factor, although it cannot be the only factor. Expanding upon a recent editorial in the Lancet, we discuss the impact of suboptimal product adherence on PrEP efficacy in the context of variable drug concentration at the exposure site, integrity of the vaginal epithelium, and the role of acute infection. © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins.
Sanghvi T.,FHI 360
Food and nutrition bulletin | Year: 2013
Alive & Thrive aims to increase exclusive breastfeeding and complementary feeding practices in Bangladesh, Ethiopia, and Vietnam. To develop and execute comprehensive communication strategies adapted to each context. We documented how three countries followed an established iterative planning process, with research steps followed by key decisions, to develop a communication strategy in each country. Secondary analysis and formative research identified the priority practices to focus on, and locally specific constraints to proper infant and young child feeding (IYCF). Communication strategies were then developed based on the social, cultural, economic, epidemiological, media use, and programmatic contexts of each country. There were widespread gaps between recommended and actual feeding practices, and these varied by country. Gaps were identified in household, community, and institutional levels of awareness and skills. Strategies were designed that would enable mothers in each specific setting to adopt practices. To improve priority behaviors, messaging and media strategies addressed the most salient behavioral determinants through face-to-face communication, social mobilization, and mass media. Trials of improved practices (TIPs), concept testing, and pretesting of materials proved useful to verify the relevance and likely effectiveness of communication messages and materials tailored for different audiences in each setting. Coordination and collaboration with multiple stakeholders from the start was important to harmonize messages and approaches, expand geographic coverage to national scale, and sustain the interventions. Our experience with designing large-scale communication strategies for behavior change confirms that systematic analysis and local planning cannot be omitted from the critical process of strategic design tailored to each context. Multiple communication channels matched to media habits in each setting can reach a substantial proportion of mothers and others who influence their IYCF practices. Preliminary data suggest that exposure to mass media plays a critical role in rapidly reaching mothers, household members, community influentials, and health workers on a large scale. Combining face-to-face interventions for mothers with social mobilization and mass media was effective in improving IYCF practices.
Aral S.O.,Centers for Disease Control and Prevention |
Cates Jr. W.,FHI 360
Sexually Transmitted Infections | Year: 2013
Development of efficacious interventions is only the first step in achieving population level impact. Efficacious interventions impact infection levels in the population only if they are implemented at the right scale. Coverage must be prioritised across subpopulations based on the diversity and clustering of infections and risk in society, and expanded rapidly without delay. It is important to prioritise those who are most likely to transmit infection first.
Ioannidis J.P.A.,Stanford Prevention Research Center |
Ioannidis J.P.A.,Stanford University |
Greenland S.,University of California at Los Angeles |
Hlatky M.A.,Stanford Prevention Research Center |
And 7 more authors.
The Lancet | Year: 2014
Correctable weaknesses in the design, conduct, and analysis of biomedical and public health research studies can produce misleading results and waste valuable resources. Small eff ects can be diffi cult to distinguish from bias introduced by study design and analyses. An absence of detailed written protocols and poor documentation of research is common. Information obtained might not be useful or important, and statistical precision or power is often too low or used in a misleading way. Insuffi cient consideration might be given to both previous and continuing studies. Arbitrary choice of analyses and an overemphasis on random extremes might aff ect the reported fi ndings. Several problems relate to the research workforce, including failure to involve experienced statisticians and methodologists, failure to train clinical researchers and laboratory scientists in research methods and design, and the involvement of stakeholders with confl icts of interest. Inadequate emphasis is placed on recording of research decisions and on reproducibility of research. Finally, reward systems incentivise quantity more than quality, and novelty more than reliability. We propose potential solutions for these problems, including improvements in protocols and documentation, consideration of evidence from studies in progress, standardisation of research eff orts, optimisation and training of an experienced and non-confl icted scientifi c workforce, and reconsideration of scientific reward systems.
Jariseta Z.R.,FHI 360
Food and nutrition bulletin | Year: 2012
Individual dietary intake data are important for informing national nutrition policy but are rarely available. National Household Consumption and Expenditures Surveys (HCES) may be an alternative method, but there is no evidence to assess their relative performance. To compare HCES-based estimates of the nutrient density of foods consumed by Ugandan women (15 to 49 years of age) and children (24 to 59 months of age) with estimates based on 24-hour recall. The 52 food items of the Uganda 2006 HCES were matched with nutrient content of foods in a 2008 24-hour recall survey, which were used to refine the HCES-based estimates of nutrient intakes. Two methods were used to match the surveys'food items. Model 1 identified the four or five most commonly consumed foods from the 24-hour recall survey and calculated their unweighted average nutrient contents. Model 2 used the nutrient contents of the single most consumed food from the 24-hour recall. For each model, 14 estimates of nutrient densities of the diet were made and 84 differences were compared. Models 1 and 2 were not significantly different. Of the model 2 HCES-24-hour recall comparisons, 67 (80%) did not find a significant difference. No significant differences were found for protein, fat, fiber, iron, thiamin, riboflavin, and vitamin B6 intakes. HCES overestimated intakes of vitamins C and B12 and underestimated intakes of vitamin A,folate, niacin, calcium, and zinc in at least one of the groups. The HCES-based estimates are a relatively good proxy for 24-hour recall measures of nutrient density of the diet. Further work is needed to ascertain nutrient adequacy using this method in several countries.