Rural secondary-school bursary disbursement delays and girls' early marriage in Zambian districts: a regression-discontinuity analysis of bursary-cutoff thresholds

Rural secondary-school bursary programmes in Zambia ration support through eligibility cutoffs, and administrative delays in disbursement have been widely reported. Whether those delays alter girls' early-marriage outcomes near the cutoff has not been established, because the design required to answer the question has not been characterised. The design treats the bursary eligibility score as the running variable and compares girls just above and just below the cutoff, with disbursement delay as a secondary moderator. Because no observational data are used, the paper characterises the operating characteristics of the design under a declared variance structure: between-cluster standard deviation 6.0, residual standard deviation 4.5, and intraclass correlation 0.64. 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. The analysis indicates that 52 clusters are required to detect a 5-percentage-point effect at 80% power under this variance structure. The contribution is a design specification and power characterisation that future fieldwork can implement, not an estimate of the effect of bursary delays on early marriage.