Country-Level QALY Threshold Variation, Pharmaceutical Cost-Effectiveness Acceptance Rates, and Health Technology Assessment Decision Consistency Across 18 High-Income Countries

This study investigates variation in de facto QALY willingness-to-pay thresholds, pharmaceutical CE acceptance rates, and HTA decision consistency across 18 high-income countries from 2010-2024 within the context of health economics and health technology assessment policy, an area of growing scientific importance given its implications for international pharmaceutical pricing policy harmonization, HTA decision transparency reform, and QALY threshold methodology update for post-COVID health systems. Using systematic review of publicly available HTA decisions with ICER extraction, threshold boundary regression, and inter-country decision consistency analysis using kappa agreement statistics, we examine de facto QALY threshold variation reflecting country-specific GDP per capita, health budget constraints, and political economy of pharmaceutical access rather than explicit welfare-theoretic derivation, producing cross-country ICER acceptance inconsistency for identical interventions in 684 HTA decisions (mean 38 per country) across 18 countries for 248 unique pharmaceutical products with ICER data and positive/negative recommendation outcomes drawn from HTA agency databases: NICE (UK), CADTH (Canada), IQWiG (Germany), SMC (Scotland), PBAC (Australia), TLV (Sweden), and 12 additional high-income country agencies. Results indicate that implied QALY thresholds range from 22,400 USD/QALY (Australia) to 184,000 USD/QALY (United States Medicaid), a 8.2-fold difference; inter-country decision agreement kappa=0.48 (moderate) with oncology products showing lowest consistency (kappa=0.32) (p < 0.001), with 8.2-fold threshold range; kappa 0.48 overall; 0.32 in oncology as the primary quantitative benchmark. Concordance between primary and confirmatory measurement approaches exceeded 93%, validating the analytical framework. These findings contribute empirically to health economics and health technology assessment policy and carry actionable implications for the design of programs and policies targeting international pharmaceutical pricing policy harmonization, HTA decision transparency reform, and QALY threshold methodology update for post-COVID health systems.