Using antecedents of medical care to develop valid quality of care measures.

OBJECTIVE: To present a new model for using the antecedents of medical care in outcomes assessment to develop valid quality of care measures.
METHODS: The pertinent literature describing the history of outcomes assessment and the influence of patient and environmental risk factors on health status were reviewed.
RESULTS: Past outcomes assessment studies have not consistently demonstrated a correlation between the processes and the outcomes of care. The use of the model described in this article indicates that the lack of correlation between process and outcome is probably because past outcomes assessment studies lacked the inclusion of medical care antecedents (primarily patient and environmental risk factors) that had a significant influence on the outcomes measured. Included is a description of a study that tests the utility of incorporating the antecedents of medical care into outcomes assessment to develop valid quality of care measures.
CONCLUSION: The model presented in this article advances quality of care measure development by using: (i) qualitative research to characterize the pertinent antecedents of medical care; and (ii) as many of the pertinent antecedents of medical care as possible to develop risk adjustment models for measuring outcomes that are more likely to identify the true linkages between the processes and outcomes of care. Knowing the linkages between the processes and outcomes of care would provide the information needed to develop valid quality of care measures, so that quality can be measured accurately and the groundwork for its improvement can be laid.