Contrast nephropathy is associated with increased in-hospital morbidity and mortality and leads to extension of hospital stay in patients with chronic renal insufficiency. Acetylcysteine seems to be a safe and inexpensive way to reduce contrast nephropathy. We aimed to assess the efficacy of acetylcysteine to prevent contrast nephropathy after administration of radiocontrast media in patients with chronic renal insufficiency.

Oxidised LDL is thought to play an important part in the pathogenesis of atherosclerosis. Observational studies have associated alpha tocopherol (vitamin E), beta carotene, or both, with reductions in cardiovascular events, but not clinical trials. We did a meta-analysis to assess the effect of these compounds on long-term cardiovascular mortality and morbidity.

Controversy exists as to whether neoadjuvant chemotherapy improves survival in patients with invasive bladder cancer, despite randomised controlled trials of more than 3000 patients. We undertook a systematic review and meta-analysis to assess the effect of such treatment on survival in patients with this disease.

The clearest advantage of new generation, atypical antipsychotics is a reduced risk of extrapyramidal side-effects (EPS), compared with conventional compounds. These findings might have been biased by the use of the high-potency antipsychotic haloperidol as a comparator in most of the trials. We aimed to establish whether the new drugs induce fewer EPS than low-potency conventional antipsychotics.

Our aim was to assess the strength of the controversial association between thrombophilia and fetal loss, and to examine whether it varies according to the timing or definition of fetal loss.

We aimed to review published work for the efficacy and safety of electroconvulsive therapy (ECT) with simulated ECT, ECT versus pharmacotherapy, and different forms of ECT for patients with depressive illness.

Advances in human genetics could help us to assess prognosis on an individual basis and to optimise the management of complex diseases. However, different studies on the same genetic association sometimes have discrepant results. Our aim was to assess how often large studies arrive at different conclusions than smaller studies, and whether this situation arises more frequently when findings of first published studies disagree with those of subsequent research.

Recombinant interferons have been approved by many national regulatory agencies for treatment of relapsing remitting multiple sclerosis, but widespread discussion continues about their true effectiveness, benefits, side-effects, and costs.

Endarterectomy reduces risk of stroke in certain patients with recently symptomatic internal carotid stenosis. However, investigators have made different recommendations about the degree of stenosis above which surgery is effective, partly because of differences between trials in the methods of measurement of stenosis. To accurately assess the overall effect of surgery, and to increase power for secondary analyses, we pooled trial data and reassessed carotid angiograms.

The age-specific relevance of blood pressure to cause-specific mortality is best assessed by collaborative meta-analysis of individual participant data from the separate prospective studies.

Falls in levels of measles, mumps, and rubella (MMR) immunisation in the UK and the continuing debate on how to respond to this situation emphasise the importance of identifying and understanding the factors that affect the uptake of recommended childhood immunisations. Both qualitative and quantitative evidence could be useful in this process. We aimed to explore the feasibility and value of an approach to formal synthesis of qualitative and quantitative evidence in the context of factors affecting the uptake of childhood immunisation in developed countries. We used a Bayesian approach to meta-analysis. Evidence from 11 qualitative and 32 quantitative studies of factors affecting uptake of childhood immunisation was combined and assessed. We conclude that use of either qualitative or quantitative research alone might not identify all relevant factors, or might result in inappropriate judgments about their importance, and could thus lead to inappropriate formulation of evidence-based policy. Further development of our methods might enable rigorous synthesis of qualitative and quantitative evidence in this and other contexts.

Results from a retrospective analysis of the Studies of Left Ventricular Dysfunction (SOLVD) study suggest that angiotensin-converting-enzyme (ACE) inhibitors may be less effective in patients receiving aspirin. We aimed to confirm or refute this theory.

Despite conflicting research findings and uncertain efficacy, single session debriefing is standard clinical practice after traumatic events. We aimed to assess the efficacy of this intervention in prevention of chronic symptoms of post-traumatic stress disorder and other disorders after trauma.

Trials on the effect of systemic chemotherapy on survival and recurrence in adults with high-grade glioma have had inconclusive results. We undertook a systematic review and meta-analysis to assess the effects of such treatment on survival and recurrence.

To obtain more reliable and precise estimates of the effect of direct thrombin inhibitors in the management of acute coronary syndromes, including patients undergoing percutaneous coronary intervention, we undertook a meta-analysis based on individual patients' data from randomised trials comparing a direct thrombin inhibitor (hirudin, bivalirudin, argatroban, efegatran, or inogatran) with heparin.

Platelet glycoprotein IIb/IIIa inhibitors have been shown to reduce cardiac complications in patients undergoing percutaneous coronary intervention. The clinical efficacy of these drugs in acute coronary syndromes, however, is still unclear. We did a meta-analysis of all large randomised trials designed to study the clinical efficacy and safety of glycoprotein IIb/IIIa inhibitors in patients with acute coronary syndromes who were not routinely scheduled to undergo early coronary revascularisation.

The relation between H pylori infection and use of non-steroidal anti-inflammatory drugs (NSAIDs) in the pathogenesis of peptic-ulcer disease is controversial. We undertook a meta-analysis to address this issue.

UK government proposals to reduce the risks posed by people with "dangerous" severe personality disorders (DSPD) include a new legal framework for indeterminate detention. We aimed to establish the degree to which those operating the framework will be able to predict which people will act violently in the future.

The triptans, selective serotonin 5-HT(1B/1D) agonists, are very effective acute migraine drugs with a well- developed scientific rationale. Seven different triptans will soon be clinically available, making evidence-based selection guidelines necessary. Triptan trials have similar designs, facilitating meta-analysis; this will provide a foundation for using triptans in clinical practice.

Whether antihypertensive drugs offer cardiovascular protection beyond blood pressure lowering has not been established. We aimed to investigate whether pharmacological properties of antihypertensive drugs or reduction of systolic pressure accounted for cardiovascular outcome in hypertensive or high-risk patients.