Randomized clinical trial (RCT) is the gold standard study for the evaluation of health interventions and is considered the second level of evidence for clinical decision making. However, the quality of the evidence produced by these studies is dependent on the methodological rigor employed at every stage of their execution. The purpose of randomization is to create groups that are comparable independent of any known or unknown potential confounding factor. A critical evaluation of the literature reveals that, for many years, RCTs have been developed based on inaccurate methodological criteria, and empirical evidence began to accumulate. Thus, guidelines were developed to assist authors, reviewers, and editors in the task of developing and assessing the methodological consistency of this type of study. The objective of this article is to review key aspects to design a good-quality RCT, supporting the scientific community in the production of reliable evidence and favoring clinical decision making to allow the patient to receive the best health care.
Keywords: Clinical trial; evidence-based dentistry; evidence-based medicine; evidence-based nursing; methods.