Are Changes in Medical Group Practice Characteristics Over Time Associated With Medicare Spending and Quality of Care?

Physician practices have been growing in size, and becoming more commonly owned by hospitals, over time. We use survey data on physician practices surveyed at two points in time, linked to Medicare claims data, to investigate whether changes in practice size or ownership are associated with changes in the use of care management, health information technology (HIT), or quality improvement processes. We find that practice growth and becoming hospital-owned are associated with adoption of more quality improvement processes, but not with care management or HIT. We then investigate whether growth or becoming hospital-owned are associated with changes in Medicare spending, 30-day readmission rates, or ambulatory care sensitive admission rates. We find little evidence for associations with practice size and ownership, but the use of care management practices is associated with lower rates of ambulatory care sensitive admissions.