[Validation of diagnostic scales of family functioning for use in primary health care services].

Care provided to patients in primary health services should include both a physical and a psychological assessment. In many cases treatment success depends on understanding individuals and their interactions, especially within the family; it is important for health professionals to be trained in this area. We investigated the validity of three well-known diagnostic scales of family functioning from the United States of America (FACES III, Beavers-Timberlawn, and GARF) for use in our setting in Porto Alegre, Brazil. The three scales were used with 31 families and compared to the results from clinical evaluations (semistructured family interviews), which were considered the gold standard. FACES III was also used with a sample of 102 families in the community. The Beavers-Timberlawn and GARF scales were strongly and positively correlated with the clinical evaluations. In contrast, our results suggest that FACES III is not a useful screening tool in primary care to detect the risk of psychiatric disorders. The Beavers-Timberlawn and GARF instruments showed great usefulness for formulating and classifying diagnoses of family functioning.