302 research outputs found
Who Shares? Who Doesn't? Factors Associated with Openly Archiving Raw Research Data
Many initiatives encourage investigators to share their raw datasets in hopes of increasing research efficiency and quality. Despite these investments of time and money, we do not have a firm grasp of who openly shares raw research data, who doesn't, and which initiatives are correlated with high rates of data sharing. In this analysis I use bibliometric methods to identify patterns in the frequency with which investigators openly archive their raw gene expression microarray datasets after study publication
The development and validation of a method using high-resolution mass spectrometry (HRMS) for the qualitative detection of antiretroviral agents in human blood
Antiretroviral drugs are used for the treatment and prevention of HIV infection. Non-adherence to antiretroviral drug regimens can compromise their clinical efficacy and lead to emergence of drug-resistant HIV. Clinical trials evaluating antiretroviral regimens for HIV treatment and prevention can also be compromised by poor adherence and non-disclosed off-study antiretroviral drug use. This report describes the development and validation of a high throughput, qualitative method for the identification of antiretroviral drugs using high-resolution mass spectrometry (HRMS) for the retrospective assessment of off-study antiretroviral drug use and the determination of potential antiretroviral therapy (ART) non-compliance
Evaluation of a Multidrug Assay for Monitoring Adherence to a Regimen for HIV Preexposure Prophylaxis in a Clinical Study, HIV Prevention Trials Network 073
ABSTRACT Daily oral tenofovir disoproxil fumarate (TDF)-emtricitabine (FTC) is a safe and effective intervention for HIV preexposure prophylaxis (PrEP). We evaluated the performance of a qualitative assay that detects 20 antiretroviral (ARV) drugs (multidrug assay) in assessing recent PrEP exposure (detection limit, 2 to 20 ng/ml). Samples were obtained from 216 Black men who have sex with men (208 HIV-uninfected men and 8 seroconverters) who were enrolled in a study in the United States evaluating the acceptability of TDF-FTC PrEP (165 of the uninfected men and 5 of the seroconverters accepted PrEP). Samples from 163 of the 165 HIV-uninfected men who accepted PrEP and samples from all 8 seroconverters were also tested for tenofovir (TFV) and FTC using a quantitative assay (detection limit for both drugs, 0.31 ng/ml). HIV drug resistance was assessed in seroconverter samples. The multidrug assay detected TFV and/or FTC in 3 (1.4%) of the 208 uninfected men at enrollment, 84 (40.4%) of the 208 uninfected men at the last study visit, and 1 (12.5%) of the 8 seroconverters. No other ARV drugs were detected. The quantitative assay confirmed all positive results from the multidrug assay and detected TFV and/or FTC in 9 additional samples (TFV range, 0.65 to 16.5 ng/ml; FTC range, 0.33 to 14.6 ng/ml). Resistance mutations were detected in 4 of the 8 seroconverter samples. The multidrug assay had 100% sensitivity and specificity for detecting TFV and FTC at drug concentrations consistent with daily PrEP use. The quantitative assay detected TFV and FTC at lower levels, which also might have provided protection against HIV infection
The impact of Cochrane Systematic Reviews : a mixed method evaluation of outputs from Cochrane Review Groups supported by the UK National Institute for Health Research
© 2014 Bunn et al.; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.Background: There has been a growing emphasis on evidence-informed decision making in health care. Systematic reviews, such as those produced by the Cochrane Collaboration, have been a key component of this movement. The UK National Institute for Health Research (NIHR) Systematic Review Programme currently supports 20 Cochrane Review Groups (CRGs). The aim of this study was to identify the impacts of Cochrane reviews published by NIHR funded CRGs during the years 2007-11. Methods: We sent questionnaires to CRGs and review authors, interviewed guideline developers and used bibliometrics and documentary review to get an overview of CRG impact and to evaluate the impact of a sample of 60 Cochrane reviews. We used a framework with four categories (knowledge production, research targeting, informing policy development, and impact on practice/services). Results: A total of 1502 new and updated reviews were produced by the 20 NIHR funded CRGs between 2007-11. The clearest impacts were on policy with a total of 483 systematic reviews cited in 247 sets of guidance; 62 were international, 175 national (87 from the UK) and 10 local. Review authors and CRGs provided some examples of impact on practice or services, for example safer use of medication, the identification of new effective drugs or treatments and potential economic benefits through the reduction in the use of unproven or unnecessary procedures. However, such impacts are difficult to objectively document and the majority of reviewers were unsure if their review had produced specific impacts. Qualitative data suggested that Cochrane reviews often play an instrumental role in informing guidance although a poor fit with guideline scope or methods, reviews being out of date and a lack of communication between CRGs and guideline developers were barriers to their use. Conclusions: Health and economic impacts of research are generally difficult to measure. We found that to be the case with this evaluation. Impacts on knowledge production and clinical guidance were easier to identify and substantiate than those on clinical practice. Questions remain about how we define and measure impact and more work is needed to develop suitable methods for impact analysis.Peer reviewe
The postdigital challenge of redefining academic publishing from the margins
This paper explores relationships between knowledge production and academic publication and shows that the current political economy of mainstream academic publishing has resulted from a complex interplay between large academic publishers, academics, and hacker-activists. The process of publishing is a form of ‘social production’ that takes place across the economy, politics and culture, all of which are in turn accommodating both old and new technology in our postdigital age. Technologies such as software cannot be separated from human labour, academic centres cannot be looked at in isolation from their margins, and the necessity of transdisciplinary approaches does not imply the disappearance of traditional disciplines. In the postdigital age, the concept of the margins has not disappeared, but it has become somewhat marginal in its own right. We need to develop a new language of describing what we mean by ‘marginal voices’ in the social relations between knowledge production and academic publication. Universities require new strategies for cohabitation of, and collaboration between, various socio-technological actors, and new postdigital politics and practice of knowledge production and academic publishing
Determination of HIV status and identification of incident HIV infections in a large, community-randomized trial: HPTN 071 (PopART).
INTRODUCTION: The HPTN 071 (PopART) trial evaluated the impact of an HIV combination prevention package that included "universal testing and treatment" on HIV incidence in 21 communities in Zambia and South Africa during 2013-2018. The primary study endpoint was based on the results of laboratory-based HIV testing for>Â 48,000 participants who were followed for up to three years. This report evaluated the performance of HIV assays and algorithms used to determine HIV status and identify incident HIV infections in HPTN 071, and assessed the impact of errors on HIV incidence estimates. METHODS: HIV status was determined using a streamlined, algorithmic approach. A single HIV screening test was performed at centralized laboratories in Zambia and South Africa (all participants, all visits). Additional testing was performed at the HPTN Laboratory Center using antigen/antibody screening tests, a discriminatory test and an HIV RNA test. This testing was performed to investigate cases with discordant test results and confirm incident HIV infections. RESULTS: HIV testing identified 978 seroconverter cases. This included 28 cases where the participant had acute HIV infection at the first HIV-positive visit. Investigations of cases with discordant test results identified cases where there was a participant or sample error (mixups). Seroreverter cases (errors where status changed from HIV infected to HIV uninfected, 0.4% of all cases) were excluded from the primary endpoint analysis. Statistical analysis demonstrated that exclusion of those cases improved the accuracy of HIV incidence estimates. CONCLUSIONS: This report demonstrates that the streamlined, algorithmic approach effectively identified HIV infections in this large cluster-randomized trial. Longitudinal HIV testing (all participants, all visits) and quality control testing provided useful data on the frequency of errors and provided more accurate data for HIV incidence estimates
Daily and Nondaily Oral Preexposure Prophylaxis in Men and Transgender Women Who Have Sex With Men: The Human Immunodeficiency Virus Prevention Trials Network 067/ADAPT Study
Background: Nondaily dosing of oral preexposure prophylaxis (PrEP) may provide equivalent coverage of sex events compared with daily dosing.
Methods: At-risk men and transgender women who have sex with men were randomly assigned to 1 of 3 dosing regimens: 1 tablet daily, 1 tablet twice weekly with a postsex dose (time-driven), or 1 tablet before and after sex (event-driven), and were followed for coverage of sex events with pre- and postsex dosing measured by weekly self-report, drug concentrations, and electronic drug monitoring.
Results: From July 2012 to May 2014, 357 participants were randomized. In Bangkok, the coverage of sex events was 85% for the daily arm compared with 84% for the time-driven arm (P = .79) and 74% for the event-driven arm (P = .02). In Harlem, coverage was 66%, 47% (P = .01), and 52% (P = .01) for these groups. In Bangkok, PrEP medication concentrations in blood were consistent with use of ≥2 tablets per week in >95% of visits when sex was reported in the prior week, while in Harlem, such medication concentrations occurred in 48.5% in the daily arm, 30.9% in the time-driven arm, and 16.7% in the event-driven arm (P < .0001). Creatinine elevations were more common in the daily arm (P = .050), although they were not dose limiting.
Conclusions: Daily dosing recommendations increased coverage and protective drug concentrations in the Harlem cohort, while daily and nondaily regimens led to comparably favorable outcomes in Bangkok, where participants had higher levels of education and employment
Demographics of sources of HIV-1 transmission in Zambia: a molecular epidemiology analysis in the HPTN 071 PopART study
BACKGROUND: In the last decade, universally available antiretroviral therapy (ART) has led to greatly improved health and survival of people living with HIV in sub-Saharan Africa, but new infections continue to appear. The design of effective prevention strategies requires the demographic characterisation of individuals acting as sources of infection, which is the aim of this study. METHODS: Between 2014 and 2018, the HPTN 071 PopART study was conducted to quantify the public health benefits of ART. Viral samples from 7124 study participants in Zambia were deep-sequenced as part of HPTN 071-02 PopART Phylogenetics, an ancillary study. We used these sequences to identify likely transmission pairs. After demographic weighting of the recipients in these pairs to match the overall HIV-positive population, we analysed the demographic characteristics of the sources to better understand transmission in the general population. FINDINGS: We identified a total of 300 likely transmission pairs. 178 (59·4%) were male to female, with 130 (95% CI 110-150; 43·3%) from males aged 25-40 years. Overall, men transmitted 2·09-fold (2·06-2·29) more infections per capita than women, a ratio peaking at 5·87 (2·78-15·8) in the 35-39 years source age group. 40 (26-57; 13·2%) transmissions linked individuals from different communities in the trial. Of 288 sources with recorded information on drug resistance mutations, 52 (38-69; 18·1%) carried viruses resistant to first-line ART. INTERPRETATION: HIV-1 transmission in the HPTN 071 study communities comes from a wide range of age and sex groups, and there is no outsized contribution to new infections from importation or drug resistance mutations. Men aged 25-39 years, underserved by current treatment and prevention services, should be prioritised for HIV testing and ART. FUNDING: National Institute of Allergy and Infectious Diseases, US President's Emergency Plan for AIDS Relief, International Initiative for Impact Evaluation, Bill & Melinda Gates Foundation, National Institute on Drug Abuse, and National Institute of Mental Health
Development of Methods for Cross-Sectional HIV Incidence Estimation in a Large, Community Randomized Trial
Background
Accurate methods of HIV incidence determination are critically needed to monitor the epidemic and determine the population level impact of prevention trials. One such trial, Project Accept, a Phase III, community-randomized trial, evaluated the impact of enhanced, community-based voluntary counseling and testing on population-level HIV incidence. The primary endpoint of the trial was based on a single, cross-sectional, post-intervention HIV incidence assessment.
Methods and Findings
Test performance of HIV incidence determination was evaluated for 403 multi-assay algorithms [MAAs] that included the BED capture immunoassay [BED-CEIA] alone, an avidity assay alone, and combinations of these assays at different cutoff values with and without CD4 and viral load testing on samples from seven African cohorts (5,325 samples from 3,436 individuals with known duration of HIV infection [1 month to >10 years]). The mean window period (average time individuals appear positive for a given algorithm) and performance in estimating an incidence estimate (in terms of bias and variance) of these MAAs were evaluated in three simulated epidemic scenarios (stable, emerging and waning). The power of different test methods to detect a 35% reduction in incidence in the matched communities of Project Accept was also assessed. A MAA was identified that included BED-CEIA, the avidity assay, CD4 cell count, and viral load that had a window period of 259 days, accurately estimated HIV incidence in all three epidemic settings and provided sufficient power to detect an intervention effect in Project Accept.
Conclusions
In a Southern African setting, HIV incidence estimates and intervention effects can be accurately estimated from cross-sectional surveys using a MAA. The improved accuracy in cross-sectional incidence testing that a MAA provides is a powerful tool for HIV surveillance and program evaluation
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Correlates of HIV Acquisition in a Cohort of Black Men Who Have Sex with Men in the United States: HIV Prevention Trials Network (HPTN) 061
Background: Black men who have sex with men (MSM) in the United States (US) are affected by HIV at disproportionate rates compared to MSM of other race/ethnicities. Current HIV incidence estimates in this group are needed to appropriately target prevention efforts. Methods: From July 2009 to October 2010, Black MSM reporting unprotected anal intercourse with a man in the past six months were enrolled and followed for one year in six US cities for a feasibility study of a multi-component intervention to reduce HIV infection. HIV incidence based on HIV seroconversion was calculated as number of events/100 person-years. Multivariate proportional hazards modeling with time-dependent covariates was used to identify correlates of HIV acquisition. Results: Of 1,553 Black MSM enrolled, 1,164 were HIV-uninfected at baseline and included in follow-up. Overall annual HIV incidence was 3.0% (95% confidence interval (CI): 2.0, 4.4%) and 5.9% among men ≤30 years old (95% CI: 3.6, 9.1%). Men ≤30 years old reported significantly higher levels of sexual risk and were more likely to have a sexually transmitted infection diagnosed during follow-up. Younger men also were more likely to not have a usual place for health care, not have visited a health care provider recently, and to have unmet health care needs. In multivariate analysis, age ≤30 years (hazard ratio (HR): 3.4; 95% CI: 1.4, 8.3) and unprotected receptive anal intercourse with HIV-positive or unknown status partners (HR: 4.1; 95% CI: 1.9, 9.1) were significantly associated with HIV acquisition. Conclusion: In the largest cohort of prospectively-followed Black MSM in the US, HIV incidence was high, particularly among young men. Targeted, tailored and culturally appropriate HIV prevention strategies incorporating behavioral, social and biomedical based interventions are urgently needed to lower these rates
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