A clinical trial involves the study of the safety, efficacy and/or dosage regimen of a therapeutic intervention (such as a drug) in humans selected according to predetermined criteria of eligibility (such as a defined severity of a specific disease), who are observed for predefined evidence of favourable and unfavourable effects. clinical trial is dedicated to advancing knowledge on the design and conduct of clinical trial related research methodologies. Covering the design, conduct, analysis, synthesis and evaluation of key methodologies, the journal remains on the cusp of the latest topics, including ethics, regulation and policy impact.