[A patient classification system for our primary care: the ambulatory care groups (ACGs)]. / Un sistema de clasificación de pacientes para nuestra atención primaria: los "ambulatory care groups" (ACGs).

OBJECTIVES: The ambulatory care groups (ACGs) were developed at the Johns Hopkins University in 1987 and they differ from other systems because their longitudinal approach and its capability to describe the case-mix of a population of reference. This paper describes the ACGs and assess its potential application to spanish primary care (PC). METHODS: Observational study with the voluntary participation of 13 physicians (general practitioner and paediatrician) and nursing staff. During six months all diagnoses and interventions to a sample of attended patients were gathered. RESULTS: The first stage in grouping involves ascribing one of the 34 ambulatory diagnostic groups (ADGs) to each of the health problems attended. The second stage involves, after several intermediates steps, assigning one of the 51 ACGs to each patient. The total number of episodes was 7,559 (input), the number of patients (output) 2,467, the ICD codes with error 292, and the number of patients with ICD codes with error 278. With 5 ACGs we classify 44% of all the patients and with 10 ACGs, 64% of all them. Only two ACGs were empty. The article explores the potential applications of the system in spanish PC: for provider financing when a capitation payment component were introduced, utilization review and quality assurance when we compare several providers or populations, and research interested to link the process and its outcomes. CONCLUSIONS: Among the various patients classification system for grouping ambulatory care, the ambulatory care groups (ACGs) appear as the method with more potentialities to PC in Spain. The ACGs should be validated before been applied and its adaption to a more suitable PC classification of diagnoses would assists its extension.