If you say so: Perceived and measured effects of hospital mergers on quality of care

Hospital markets are becoming increasingly consolidated despite mixed evidence regarding the desirability of hospital mergers. This study seeks to advance the understanding of hospital mergers by studying both their perceived and measured effects on quality of care. We used a mixed-methods approach to study hospital mergers in the Netherlands. In the quantitative stage we tested the effect of hospital mergers (approved between 2008 and 2014) on 82 quality indicators (11 at hospital level, 28 at department level, and 43 at disease level) using a difference-in-difference approach. Qualitatively, three case studies were conducted to study how hospital executives, hospital managers, and healthcare professionals perceive a merger to have impacted quality of care. Fifteen quality indicators proved significantly worse in merged hospitals (three after applying Bonferroni correction) and two quality indicators proved significantly better in merged hospitals (none after applying Bonferroni correction). The majority...