[Reading a clinical trial report]

To improve medical knowledge by reading clinical trial reports it is necessary to check for the respect of the methodological rules, and to analyze and criticize the results. A control group and a randomisation are always necessary. Double blind assessment, sample size calculation, intention to treat analysis, a unique primary end point are also important. The conclusions of the trial are valid only for the population included and the clinical signification of the results, depending on the control treatment, has to be evaluated. Respect of the reading rules is necessary to assess the reliability of the conclusions, in order to promote evidence-based practice.