District Hospital Trauma Chaplaincy Visit Timing and Post-Traumatic Stress Symptom Persistence Among Rwandan Survivors: A Target-Trial Emulation of Spiritual Care Scheduling Windows

The timing of trauma chaplaincy visits within district hospital admissions has been proposed as a modifiable determinant of post-traumatic stress symptom persistence among Rwandan survivors, yet the causal contrast that chaplaincy scheduling actually defines has not been formalised. the present analysis treats the question as a target-trial emulation problem and characterises the operating characteristics of a before-after-control-impact design under a declared variance structure. The design uses eight, sixteen, twenty-four and thirty-two clusters, effect sizes of three, five and eight percentage points, and two thousand replications per design cell. The between-cluster standard deviation was 6.0, the residual standard deviation was 4.5, and the intraclass correlation was 0.64. Power was estimated across the design grid, and the minimum detectable effect at eighty per cent power was derived for each cluster count. Fifty-two clusters were required to detect a five percentage point effect at eighty per cent power. The before-after-control-impact estimator is sensitive to cluster count in the range that district hospital networks can realistically supply, and that the intraclass correlation of 0.64 imposes a substantial design penalty. Chaplaincy scheduling studies should be planned as cluster-level designs with explicit variance assumptions rather than as individually randomised trials, and it specifies the scheduling windows that such designs can credibly evaluate.