A Retrospective Analysis of the Clinical Quality Effects of the Acquisition of Highland Park Hospital by Evanston Northwestern Healthcare

In 2004, the Federal Trade Commission brought a legal action retrospectively challenging the 2000 acquisition of Highland Park Hospital by Evanston Northwestern Healthcare in Evanston, Illinois. A major issue in that case was whether the merger had resulted in improved clinical quality at Highland Park. In this paper, we describe the conceptual framework that guided our analysis of that issue and we report our findings. Specifically, we examine numerous quantitative measures of clinical quality. We find little evidence that the merger improved quality. We also discuss the applicability of our framework to the prospective analysis of unconsummated hospital mergers.