A5015955757- HIV/AIDS Research and Interventions
- Meta-analysis and systematic reviews
- HIV-related health complications and treatments
- HIV Research and Treatment
- HIV/AIDS drug development and treatment
- Health Systems, Economic Evaluations, Quality of Life
- COVID-19 Clinical Research Studies
- Advanced Causal Inference Techniques
- Statistical Methods in Clinical Trials
- Asthma and respiratory diseases
- SARS-CoV-2 and COVID-19 Research
- Oral microbiology and periodontitis research
- Vaccine Coverage and Hesitancy
- Statistical Methods and Bayesian Inference
- Long-Term Effects of COVID-19
- Neonatal Respiratory Health Research
- Health disparities and outcomes
- Birth, Development, and Health
- Tuberculosis Research and Epidemiology
- Delphi Technique in Research
- Healthcare Policy and Management
- Statistical Methods and Inference
- Venous Thromboembolism Diagnosis and Management
- Atrial Fibrillation Management and Outcomes
- Salivary Gland Disorders and Functions
University of Bristol
2016-2025
NIHR Bristol Biomedical Research Centre
2018-2025
Health Data Research UK
2020-2025
University Hospitals Bristol NHS Foundation Trust
2018-2024
National Institute for Health Research
2017-2024
Stanford University
2024
Berkeley College
2024
National Health Service
2024
University of Oxford
2020-2022
London School of Hygiene & Tropical Medicine
1992-2022
Flaws in the design, conduct, analysis, and reporting of randomised trials can cause effect an intervention to be underestimated or overestimated. The Cochrane Collaboration's tool for assessing risk bias aims make process clearer more accurate
Non-randomised studies of the effects interventions are critical to many areas healthcare evaluation, but their results may be biased. It is therefore important understand and appraise strengths weaknesses. We developed ROBINS-I ("Risk Of Bias In Studies - Interventions"), a new tool for evaluating risk bias in estimates comparative effectiveness (harm or benefit) from that did not use randomisation allocate units (individuals clusters individuals) comparison groups. The will particularly...
Most studies have some missing data. Jonathan Sterne and colleagues describe the appropriate use reporting of multiple imputation approach to dealing with them
Funnel plots, and tests for funnel plot asymmetry, have been widely used to examine bias in the results of meta-analyses. asymmetry should not be equated with publication bias, because it has a number other possible causes. This article describes how interpret recommends appropriate tests, explains implications choice meta-analysis model
Observational epidemiological studies suffer from many potential biases, confounding and reverse causation, this limits their ability to robustly identify causal associations. Several high-profile situations exist in which randomized controlled trials of precisely the same intervention that has been examined observational have produced markedly different findings. In other sciences, use instrumental variable (IV) approaches one approach strengthening inferences non-experimental situations....
BackgroundWorld Health Organization expert groups recommended mortality trials of four repurposed antiviral drugs — remdesivir, hydroxychloroquine, lopinavir, and interferon beta-1a in patients hospitalized with coronavirus disease 2019 (Covid-19).MethodsWe randomly assigned inpatients Covid-19 equally between one the trial drug regimens that was locally available open control (up to five options, active local standard care). The intention-to-treat primary analyses examined in-hospital...
<b>Objective</b> To examine whether the association of inadequate or unclear allocation concealment and lack blinding with biased estimates intervention effects varies nature outcome. <b>Design</b> Combined analysis data from three meta-epidemiological studies based on collections meta-analyses. <b>Data sources</b> 146 meta-analyses including 1346 trials examining a wide range interventions outcomes. <b>Main outcome measures</b> Ratios odds ratios quantifying degree bias associated...
Publication bias and related in meta-analysis is often examined by visually checking for asymmetry funnel plots of treatment effect against its standard error. Formal statistical tests plot have been proposed, but when applied to binary outcome data these can give false-positive rates that are higher than the nominal level some situations (large effects, or few events per trial, all trials similar sizes). We develop a modified linear regression test based on efficient score variance,...
T he NHS R&D Health Technology Assessment (HTA) Programme was set up in 1993 to ensure that high-quality research information on the costs, effectiveness and broader impact of health technologies is produced
Published evidence suggests that aspects of trial design lead to biased intervention effect estimates, but findings from different studies are inconsistent. This study combined data 7 meta-epidemiologic and removed overlaps derive a final set 234 unique meta-analyses containing 1973 trials. Outcome measures were classified as "mortality," "other objective," "or subjective," Bayesian hierarchical models used estimate associations characteristics with average bias between-trial heterogeneity....
Mendelian randomisation analyses use genetic variants as instrumental variables (IVs) to estimate causal effects of modifiable risk factors on disease outcomes. Genetic typically explain a small proportion the variability in factors; hence can require large sample sizes. However, an increasing number have been found be robustly associated with disease-related outcomes genome-wide association studies. Use multiple instruments improve precision IV estimates, and also permit examination...
BackgroundHealth care for people living with HIV has improved substantially in the past two decades. Robust estimates of how these improvements have affected prognosis and life expectancy are utmost importance to patients, clinicians, health-care planners. We examined changes 3 year survival patients starting combination antiretroviral therapy (ART) between 1996 2013.MethodsWe analysed data from 18 European North American HIV-1 cohorts. Patients (aged ≥16 years) were eligible this analysis...
This article describes updates of the meta-analysis command metan and options that have been added since command's original publication (Bradburn, Deeks, Altman, – an alternative command, Stata Technical Bulletin Reprints, vol. 8, pp. 86–100). These include version 9 graphics with flexible display options, ability to meta-analyze precalculated effect estimates, analyze subgroups by using by() option. Changes output, saved variables, results are also described.