Is quality free? The relationship between cost and quality across 18 provider groups

Objective: To learn whether the healthcare costs for patients of various care delivery systems are associated with the quality of ambulatory care received. Despite intense interest in the cost and quality of healthcare delivery in the United States, there have been relatively few studies of the relationship between those measures, and none have addressed the relationship for integrated care delivery systems. Study design: Results of a retrospective analysis of claims records for overall costs of care for enrollees of 18 care delivery systems were compared with a variety of quality measures for each system. Patients and methods: We analyzed the yearly (1996-1998) claims records of 110,000 to 150,000 employees and dependents of member companies of an employer coalition in Minnesota that received all of their medical services from 18 care systems that had at least 1000 employees and dependents. Overall case-mix and inflation-adjusted costs of care for enrollees of each care system were compared with 21 ambulatory care process-oriented quality indicators covering 3 chronic diseases and 5 preventive services. Results: Regardless of whether the unit of analysis was the care system or the individual enrollee, there was no evidence of a consistent relationship between overall cost of care and quality on any measures. The little association there was tended to suggest that higher quality was provided by the lowest-cost care systems. Conclusion: Although additional confirmatory research is needed, this analysis of the quality-cost relationship provides some reassurance for those who question whether selecting lower-cost sources of medical care might have a negative effect on quality of care.