Comparison of HTA Appraisal Outcomes in Japan, the UK, and Canada: A Cross-Sectional Mapping Study

Background Japan’s cost-effectiveness evaluation (CEE) system is a health technology assessment (HTA) framework used to inform post-listing price adjustments. However, comparisons of its appraisal outputs with those of coverage-oriented HTA systems in the UK and Canada remain limited. Objectives To describe the distribution and agreement of study-defined categories assigned to HTA appraisal outputs in Japan, the UK, and Canada for Japan’s CEE-evaluated products, and to describe CEE-derived price changes in Japan by additional clinical benefit status. Methods We mapped published appraisal outputs for 43 CEE-evaluated products to 4 common categories (Positive, Conditional, Negative, Not assessed) using CEE price-adjustment decisions in Japan, appraisal or access decisions in the UK, and reimbursement recommendations in Canada. For the main analysis, only final decisions were eligible; products without one were classified as Not assessed. Direct UK-Canada population alignment was assessed post hoc. Results Conditional predominated (Japan 79.1%, UK 55.8%, Canada 65.1%), and Not assessed accounted for 23.3% in the UK and 25.6% in Canada; Negative was not applicable in Japan’s CEE framework, and no Canadian product was classified as Positive. Complete 3-jurisdiction agreement occurred in 14/43 products (32.6%) and pairwise agreement ranged from 41.9% to 60.5%; after excluding Not assessed classifications, pairwise agreement was 54.5% to 68.8%, and 3-jurisdiction agreement was 48.3%. Among pairwise comparisons, only UK-Canada exceeded the agreement expected under independent classification (60.5% vs 42.7%). Of the 19 concordant products in the direct UK-Canada alignment analysis, only 1 had fully aligned appraisal populations. The median CEE-derived price change was −4.28%; by additional clinical benefit status, medians were −1.43% (demonstrated, n = 21), −4.28% (mixed, n = 16), and −6.01% (not demonstrated, n = 6). Discussion The institutional meaning of Conditional differed: price adjustment in Japan, clinical restrictions or managed access in the UK, and reimbursement recommendations with clinical and/or pricing conditions in Canada. Mapped-category agreement should not be interpreted as evidence of similarity between HTA systems. Conclusions Mapped-category agreement coexisted with differences in institutional meaning and appraised populations. In Japan, price changes varied by additional clinical benefit status, but these differences should be interpreted under price-adjustment rules that themselves incorporate assessments of additional clinical benefit.