Persistent Differences in Reported Inpatient Rehabilitation-Bed Capacity Across 27 European and OECD Countries

Background/Objectives: Reported inpatient rehabilitation-bed stocks vary widely across countries, but their trajectories and relationship with population ageing are less clear. We examined convergence and associations with ageing in 27 European and OECD countries during 2000–2023. Methods: We combined Eurostat and OECD data into a 504-country-year panel. Analyses included sigma- and beta-convergence, the Phillips–Sul log-t test and exploratory club clustering. Monte Carlo checks used the actual panel dimensions. Mean-group, common-correlated-effects mean-group, and Driscoll–Kraay models examined associations between bed-capacity growth and changes in older-population shares. Results: Reported capacity ranged from 2.4 to 193.8 beds per 100,000 population in 2023. Panel-wide convergence was rejected, while beta-convergence estimates remained imprecise. Dispersion increased descriptively in the balanced core, but country-bootstrap intervals for its change and trend included zero. Associations between capacity growth and ageing showed no consistent positive pattern. Simulation results distinguished panel-wide testing from less stable club membership in short panels. Conclusions: Reported inpatient rehabilitation-bed capacity followed heterogeneous trajectories across the included countries. Population ageing alone did not explain capacity growth. These findings concern one component of rehabilitation provision and support joint monitoring of inpatient capacity, community services, workforce, and service use.