Figure 1.

Unique patients in the diabetes registry, by activity status, and method of assignment to the clinic group responsible for diabetes care. VISN 10 is the VA Integrated Service Network 10, which covers the state of Ohio. Patients are retained in the diabetes registry in a cumulative fashion, beginning October 1, 2001. Active patients are defined either by having a primary care clinic visit within the past 18 months or by having diabetes medications dispensed from a VISN 10 pharmacy within the past 18 months. By mapping the location of each patient's most recent primary care visit in the past 18 months to a clinic group, more patients could be assigned to a clinic group responsible for diabetes care than could be assigned by searching the tables that maintain the primary care provider assignments.