[Can the results of large-scale clinical trials be applied to clinical practice?]

The management of a patient in cardiac failure should lead the physician to ask if the patient might benefit from treatment with an angiotensin converting inhibitor. Meta-analyses give a positive reply but often lack detail. Analysis of large scale therapeutic trials is the only way to determine whether the results are applicable in an individual case. This analysis starts with validation of the methodology (correct randomisation, respect of double blind protocol, identity of groups) and synthesis of results expressed, if possible, in absolute values. In a second stage, the criteria of inclusion, exclusion, and the comorbidity of enrolled patients, should be compared with those of the patient under consideration. In addition, the amplitude of the therapeutic benefit and the importance of undesired effects must be taken into account in the therapeutic decision. This approach allows a reasoned prescription based on documented facts.