Cluster randomized trials of individual-level interventions were at high risk of bias.

ABSTRACT:

Objectives

To describe the prevalence of risks of bias in cluster-randomized trials of individual-level interventions, according to the Cochrane Risk of Bias tool.

Study design and setting

Review undertaken in duplicate of a random sample of 40 primary reports of cluster-randomized trials of individual-level interventions.

Results

The most common reported reasons for adopting cluster randomization were the need to avoid contamination (17, 42.5%) and practical considerations (14, 35%). Of the 40 trials all but one was assessed as being at risk of bias. A majority (27, 67.5%) were assessed as at risk due to the timing of identification and recruitment of participants; many (21, 52.5%) due to an apparent lack of adequate allocation concealment; and many due to selectivel

SUBMITTER: Easter C 

PROVIDER: S-EPMC8592576 | biostudies-literature | 2021 Oct

REPOSITORIES: biostudies-literature