Clarifying selection bias in cluster randomized trials

• Published in: Clinical trials (London, England) Vol. 19; no. 1; p. 33
• Main Authors: Li, Fan, Tian, Zizhong, Bobb, Jennifer, Papadogeorgou, Georgia
• Format: Journal Article
• Language: English
• Published: England 01.02.2022
• Subjects: Bias; Causality; Computer Simulation; Humans; Intention to Treat Analysis; Randomized Controlled Trials as Topic; Research Design; Selection Bias; identification bias; Average treatment effect; principal stratification; intention-to-treat; causal inference; heterogeneous treatment effect; recruitment bias

In cluster randomized trials, patients are typically recruited after clusters are randomized, and the recruiters and patients may not be blinded to the assignment. This often leads to differential recruitment and consequently systematic differences in baseline characteristics of the recruited patien...