The bigger, the better? A systematic review on the impact of mergers on primary care organizations

BACKGROUND: Primary care services are the first point of contact in a healthcare system; in the last years, many mergers and reconfigurations have taken place in this setting. The aim of this study is to summarize the literature evidence on the relationship between the increase in the size of these organizations and their performance. METHODS: A systematic review of the literature was carried out querying EMBASE, MEDLINE and Web of Science databases, from their inception to January 2020. Articles which quantitatively assessed outcomes and process indicators of merger/structural reorganization of primary care organizations and qualitative articles that assessed staff perception and satisfaction were included in the review. RESULTS: A total of 3626 articles was identified and another study was retrieved through snowball search; 11 studies were included in the systematic review. Studies about lipid profile evaluation and emergency admissions for chronic conditions showed moderate evidence in supporting the merging of primary care organizations; conversely, clinical outcome studies did not reach a sufficient level of evidence to support merging actions. A moderate evidence of a negative effect on patient's perspective was found. CONCLUSION: Actually, there is no strong evidence in favour or against merging of primary care organizations without equivocation. This review supports the possibility to identify indicators for evaluating a merging process of primary care organizations and for adopting eventual remedies during this process. Further efforts should be made to identify additional indicators to assess merge actions among primary care organizations.