Pooling Masks Lockdown Variation

When models pool data across countries (partial pooling/hierarchical models) they gain statistical power but can obscure real national and subnational differences in how and when interventions changed transmission. That tradeoff means headline claims like 'lockdowns drove R below 1 everywhere' can overstate uniform effects and understate local exceptions or alternative causal paths. — Policymakers and the public should treat cross‑country model claims as contingent on pooling assumptions because those assumptions directly affect decisions about national vs localized interventions and the political legitimacy of uniform mandates.