The double jeopardy of clustered measurement and cluster randomisation
Michael S Kramer, Richard M Martin, Jonathan A C Sterne, Stanley Shapiro, Mourad Dahhou, Robert W Platt, Michael S Kramer, Richard M Martin, Jonathan A C Sterne, Stanley Shapiro, Mourad Dahhou, Robert W Platt
Abstract
Michael S Kramer and colleagues suggest that double clustering might explain the negative results of some cluster randomised trials and describe some strategies for avoiding the problem
Conflict of interest statement
Competing interests: None declared.
Provenance and peer review: Not commissioned; externally peer reviewed.
Figures
Fig Mean (±1 SD) body mass index (top), triceps skinfold thickness (middle), and verbal IQ (bottom) in 31 participating polyclinics, in ascending order. Red horizontal lines depict the means of the 31 polyclinic means for each outcome.
References
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Source: PubMed