Community Mental Health Service Essential Medicines Stockout Duration and Antipsychotic Switching in Malawian District Clinics: A Difference-in-Differences Estimation of Supply-Chain Exposure
Year: 2026
Type: article
Abstract: Essential medicines stockouts in community mental health services are widely reported, but their behavioural consequences for prescribing remain poorly quantified. The framework treats stockout duration as a supply-chain exposure with a dose-response structure, distinguishes switching driven by clinical judgement from switching forced by unavailability, and specifies the parallel-trends and no-anticipation assumptions required for identification. Because no clinic-level dispensing or stockout data were available for this analysis, the paper is methodological rather than empirical: it formalises the exposure, defines the estimand, derives the difference-in-differences specification, and sets out the threats to validity that a field implementation would face. To anchor the design in measurable quantities, the paper draws on a real DHS Program indicator of family planning messages delivered at community meetings across fifteen African countries between 2021 and 2025, with a mean of 29.733 and a standard deviation of 17.495, to illustrate the scale of between-country heterogeneity that a multi-site supply-chain study must accommodate. The contribution is a pre-specified, falsifiable estimation strategy for linking stockout duration to antipsychotic switching, together with an explicit account of the conditions under which the resulting estimates would and would not support causal interpretation.
Authors: Mwale-Banda, Chikondi, Nkhoma, Thokozani
Institution: University of Malawi
Language: English
Subfield: Social Psychology
Field: Psychology
Domain: Social Sciences
Open Access status: green
OpenAlex ID: W7223231786