Medical Sociology of Hospital Discharge Planning Meetings and Readmission Timing in South African District Hospitals: A Stepped-Wedge Evaluation of Coordination Exposure

Stepped-wedge designs are increasingly proposed for evaluating hospital discharge planning meetings in South African district hospitals, yet the before-after-control-impact estimator that such designs often imply has not been characterised under the variance structures typical of ward-level readmission timing. Power was estimated across 2000 replications per design cell for cluster counts of 8, 16, 24 and 32 and effect sizes of 3, 5 and 8 percentage points.56 clusters are required to detect a 5 percentage point effect at 80 per cent power under this variance structure, a requirement that exceeds the cluster counts typically available to district hospital evaluations. Minimum detectable effects at 80 per cent power remain above 5 percentage points for all cluster counts examined. Coordination exposure in discharge planning meetings cannot be credibly estimated by before-after-control-impact designs at feasible cluster counts, and it specifies the design conditions under which such evaluations would become informative. The contribution is a design-theoretic account of why readmission-timing studies in district hospitals systematically under-detect coordination effects, and a set of reporting requirements for future stepped-wedge evaluations.