Subjective and objective outcomes in randomized clinical trials: definitions differed in methods publications and were often absent from trial reports

Objectives The degree of bias in randomized clinical trials varies depending on whether the outcome is subjective or objective. Assessment of the risk of bias in a clinical trial will therefore often involve categorization of the type of outcome. Our primary aim was to examine how the concepts “subjective outcome” and “objective outcome” are defined in methodological publications and clinical trial reports. To put this examination into...