Meta-Analyses of Randomised Trials
In many areas of clinical medicine, it is common to find multiple randomized trials that address a similar question. Meta-analysis is a statistical technique for combining the findings of such trials. CTSU’s work on meta-analysis of randomized trials is distinctive because it typically involves analysis of large datasets of anonymised data on individual patients, rather than the more typical summaries of trial findings. The availability of such data allows detailed information to be obtained on the benefits and hazards of drugs.
Most of our meta-analyses involve international collaboration with investigators in order to frame the scientific questions and to analyse and interpret the findings. CTSU has collaborations with investigators in cancer medicine, such as the Early Breast Cancer Trialists' Collaborative Group (EBCTCG), which has helped to improve the care of patients with breast cancer by providing reliable assessments of treatments that involve some decades of follow-up from trials. In vascular disease, the work of the Cholesterol Treatment Trialists’ (CTT) Collaboration, the Antithrombotic Trialists’ (ATT) Collaboration, and the Stroke Thrombolysis Trialists’ (STT) Collaboration has helped to determine the balance of beneficial and harmful effects of drugs used for the treatment of prevention of conditions such as heart attacks and strokes. In addition, CTSU has also investigated the hazards of commonly used drugs; these include the Coxib and traditional NSAID Trialists’ (CNT) Collaboration, which has examined the cardiovascular risks of the commonest class of painkillers used for muscle and joint disorders (so-called nonsteroidal anti-inflammatory drugs –NSAIDs).
All of these international collaborations are highly influential, and their findings have been widely incorporated into treatment guidelines used by doctors in the care of their patients.
Other ongoing projects include a meta-analysis examining the effects of treatments used to prevent and treat peptic ulcer disease (such as histamine 2 receptor antagonists and proton pump inhibitors- PPIs), and the Marfan Treatment Trialists’ (MTT) Collaboration which is assessing the effects of treatments in a genetic condition known as Marfan syndrome.