Equity Effects of Medical Coverage on Avoidable Care Delays in Kenya: A Target-Trial Emulation
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Kenya's health financing reforms have expanded medical coverage, yet the equity consequences for avoidable care delays remain contested because coverage is not randomly assigned and delay is observed only for those who eventually reach care. The design is evaluated across 2000 replications per cell for cluster counts of 8, 16, 24 and 32 and effect sizes of 3, 5 and 8 percentage points, under a declared variance structure with between-cluster standard deviation of 6.0, residual standard deviation of 4.5 and intraclass correlation of 0.64. Power to detect a 5 percentage point effect reaches 80 per cent at 56 clusters. The analysis specifies the causal estimand, the eligibility criteria, the treatment strategies and the confounding adjustment that a target-trial emulation of coverage expansion would require, and it identifies the conditions under which the before-after-control-impact estimator recovers equitable rather than merely average effects. The contribution is a design specification and a power benchmark for equity-oriented causal inference on coverage and delay in Kenyan primary care, not an empirical estimate of coverage effects.
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References
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