Use of services by diabetes patients in managed care organizations - Development of a diabetes surveillance system

OBJECTIVE - To develop a diabetes surveillance system that estimates the prevalence of diabetes and characterizes service use in diverse managed care organizations (MCOs). RESEARCH DESIGN AND METHODS - Computerized inpatient, pharmacy, outpatient, and laboratory records were used to develop an algorithm to identify diabetes patients and to develop surveillance indicators common to the three participating MCOs. Using 1993 data, the availability, specifications, and limitations of various surveillance indicators were determined. RESULTS - An extensive set of diabetes surveillance indicators was identified from the four sources of data. Consistent data specifications across MCOs needed to consider variation in the type of data collected, a lack of documentation on level of coverage, differences in coding data, and different models of health care delivery. A total of 16,363 diabetes patients were identified. The age-adjusted prevalence of diabetes ranged from 24 to 29 per 1,000 enrollees. Approximately one-third of patients with diabetes (32-134%) were taking insulin. The majority had one or more visits to a primary care physician during the year (72-94%). Visits to specialists were less frequent. Ophthalmologists and optometrists were the most commonly used specialists: 29-60% of the patients with diabetes at the three MCOs had visited an ophthalmologist or optometrist. About one-fifth had an overnight hospital stay during the year. CONCLUSIONS - This diabetes surveillance system is a useful tool for MCOs to track trends in prevalence of diabetes, use of health services, and delivery of preventive care to individuals with diabetes. This system may also be useful for health care planning and for assessing use changes after new developments in diabetes care or new quality management initiatives.