Study-based registers of randomized controlled trials: Starting a systematic review with data extraction or meta-analysis.

Despite years of use of study-based registers for storing reports of randomized controlled trials (RCTs), the methodology used in developing such registers/databases has not been documented. Such registers are integral to the process of scientific reviewing. We document and discuss methodological aspects of the development and use of study-based registers.

Chlorpromazine for schizophrenia: a Cochrane systematic review of 50 years of randomised controlled trials.

Background: Chlorpromazine (CPZ) remains one of the most common drugs used for people with schizophrenia worldwide, and a benchmark against which other treatments can be evaluated. Quantitative reviews are rare; this one evaluates the effects of chlorpromazine in the treatment of schizophrenia in comparison with placebo.

Methods: We sought all relevant randomised controlled trials (RCT) comparing chlorpromazine to placebo by electronic and reference searching, and by contacting trial authors and the pharmaceutical industry.

Gross Domestic Product (GDP) and productivity of schizophrenia trials: an ecological study.

Background: The 5000 randomised controlled trials (RCTs) in the Cochrane Schizophrenia Group's database affords an opportunity to research for variables related to the differences between nations of their output of schizophrenia trials.

Methods: Ecological study--investigating the relationship between four economic/demographic variables and number of schizophrenia RCTs per country. The variable with closest correlation was used to predict the expected number of studies.