2. Do hospital mergers reduce waiting times? Theory and evidence from the English NHS

Cirulli, V., Marini, G., Marini, M. A., & Straume, O. R. (2025). Do hospital mergers reduce waiting times? Theory and evidence from the English NHS. Journal of Economic Behavior and Organization, 238. https://doi.org/10.1016/j.jebo.2025.107196The study examines both theoretically and empirically the impact of hospital mergers on waiting times in health care markets with regulated prices, using the English National Health Service (NHS) as a case study. The theoretical model adopts a spatial framework in which patients choose hospitals based on travel distance and waiting times, while hospitals maximize a weighted objective combining profits and patient welfare. The model predicts an ambiguous overall effect of mergers, as they internalize opposing competitive forces: altruistic competition, which may increase waiting times by attracting more patients, and profit-oriented competition, which may reduce waiting times by discouraging the treatment of unprofitable patients. Cost synergies can further lower waiting times when hospitals are sufficiently profit-oriented. Empirically, using 19 years of NHS panel data and a difference-in-differences approach, the study finds that mergers increase waiting times on average by 41%. However, effects are heterogeneous: mergers involving Foundation Trusts reduce waiting times substantially, while mergers among more altruistic hospitals increase them.