The Association Between Continuity of Care and the Overuse of Medical Procedures

IMPORTANCE: Both the overuse of unnecessary medical procedures and poor continuity of care are thought to contribute to high health care spending and poor patient outcomes. OBJECTIVE: To investigate the association between care continuity and use of potentially unnecessary procedures. DESIGN, SETTING, AND PARTICIPANTS: Observational retrospective cohort (n = 1,208,250 patients > 65 years) using 5% Medicare fee-for-service claims from 2008. MAIN OUTCOMES AND MEASURES: We evaluated continuity using the Bice-Boxerman continuity of care index. We measured overuse using a previously validated set of 19 potentially overused procedures. RESULTS: Altogether, 14.7% of patients received at least 1 potentially overused procedure during the calendar year. For each 0.1 increase in the continuity score (0.4 SDs), patients had 0.93 times the odds of receiving overused procedures than those with lower scores (95% CI, 0.93-0.94). Higher continuity was significantly associated with lower odds of 9 procedures (Holm-Bonferroni corrected P < .02 was significant: 6 of 13 diagnostic tests with ORs, 0.84-0.99; P < .001 and 3 therapeutic procedures with ORs 0.81-0.87; P <.001). Conversely, higher continuity was significantly associated with increased overuse for 3 procedures (1 diagnostic test OR, 1.06; P < .001, 1 of 2 screening tests OR, 1.05; P < .001, and the single monitoring test OR, 1.03; P < .01). CONCLUSIONS AND RELEVANCE: Increased continuity was associated with an overall decrease in overuse, suggesting a potential benefit of high-continuity care; however, the strength and direction of the association varied according to the specific procedure.