Clinical trials are designed as uncontrolled or controlled studies. Controlled studies, with the highest quality and level of evidence coming from randomized controlled studies, judge the efficacy of an experimental treatment against an alternative treatment, or control. Controls may be broadly categorized as placebo, active treatment, or best available therapy.1 A placebo, by definition, has no therapeutic benefit and is intended to provide only a psychological treatment effect. In comparison, active treatment or best available therapy controls have intrinsic therapeutic benefit.
Sedaghat AR, Phillips KM. Controls for Clinical Trials of Intranasal Medications for Chronic Rhinosinusitis: Who Nose What to Do? JAMA Otolaryngol Head Neck Surg. 2021;147(2):133–134. doi:10.1001/jamaoto.2020.3722
Artificial Intelligence Resource Center
Customize your JAMA Network experience by selecting one or more topics from the list below.