Adjusted Clinical Groups System Research Articles

Adjusted Clinical Groups (ACGs) explain the utilization of primary care in Spain based on information registered in the medical records: A cross-sectional study

Background Previous studies have shown the validity of Adjusted Clinical Groups (ACGs) in the primary care setting, but the absence of administrative databases is a problem for the implementation of this system. Objectives To assess the validity of physicians’ notes in computerized clinical records for the implementation of ACGs, and to determine the ability of the ACGs system to explain the use of primary care resources in real conditions of the daily practice. Research design Cross-sectional study. Subjects All patients who were continuously assigned to 56 physicians from public primary health care centers in the Bizkaia Basque Country (Spain) over at least a 6-month period were included. Measures Patients were classified by means of the ACGs system using the ICD-9-CM diagnostic codes according to three scenarios: (1) those annotated by the physicians in the computerized medical record, (2) codification of computerized medical records diagnoses by the research team, and (3) computerized medical records diagnoses complemented by hospital discharge codes. Results The ACGs system explained more than 50% of the variance in visits made to primary care physicians, 25–40% of prescriptions, 25–30% of referrals and requests of laboratory tests, and 14–16% of radiographs. The coefficients of determination remained almost invariable after the addition of hospital diagnoses or correction of coding errors. Fifty-two physicians (93%) registered their patients’ diagnosis quite acceptably, whereas only 29 (52%) included this datum in the prescriptions. Conclusions The ACGs system is a useful tool to explain the use of primary care services in a national health care system within the European Union. The implementation of ACGs from the physician's annotations in the computerized medical records is feasible.

Performance of the ACG case-mix system in two Canadian provinces.

While the adjusted clinical group (ACG) system has been extensively validated in the United States, its use in other developed nations has been limited. This article examines the performance of the system in 2 Canadian provinces and assesses the extent to which ACGs can account for same-year and next-year health care expenditures. The study population included all residents of Manitoba and British Columbia who were continuously enrolled in the provincial health plans from April 1, 1995, to March 31, 1997. ACGs were assigned through diagnoses from fee-for-service physician claims and hospital separation records. "Physician" costs were calculated from the fee-for-service tariffs, and for Manitobans, "total" costs were also computed by combining physician and hospital costs. Linear regression was used to examine the ability of the ACG system to explain variation in individual costs (truncated at the 99th percentile). The British Columbia and Manitoba data were generally acceptable, with fewer than 2% rejected diagnoses. Higher costs were associated with both the accumulation of morbidities and their relative severity. For physician costs, the ACG system explained approximately 50% and approximately 25% of the variation in same-year and next-year truncated costs, respectively. For total costs, the system explained approximately 40% and approximately 14% of these respective costs. The application of ACGs in Canada is feasible using existing data. The ability of the ACG system to explain variation in costs is similar to that found in US health systems. While application of ACGs in Canada shows promise, further research is required to examine how closely they reflect population morbidity burdens and health care needs.