Revista Colombiana de Psiquiatría
Print version ISSN 0034-7450
Introduction: Randomized Clinical Trials are used to evaluate interventions (drugs, therapies or surgical techniques), since they control for many possible sources of bias. Development: Clinical Trials must have a control group, assignation to treatment groups must be at random and it is ideal to blind the study subject, the researcher and the analyst for the evaluation. Both the experimental and the control interventions must be selected with solid bases, and there should be a genuine uncertainty about their effectiveness and safety. Outcome variables should be hard and objective, and if soft variables are used, they must be transformed using predefined methods to make them as objective as possible. If it is not possible to mask the subject or the intervention, double dummy methods should be employed or hard outcomes used.
Keywords : Randomized clinical trial; double-blind; hard outcomes; soft outcomes; assignation, ramdomization.