Measuring attributes of primary care: development of a new instrument.

BACKGROUND: The purpose of this study was to evaluate the measurement properties of an instrument developed to measure seven key aspects of the delivery of primary care from the perspective of patients visiting their family physician, and to report the association of these aspects with patient satisfaction.

METHODS: A cross-sectional study design was used to examine the responses of 2899 patients visiting 138 family physicians' offices in Northeast Ohio. A 20-item research tool, the Components of Primary Care Index (CPCI), was created to measure the domains of primary care based on the new Institute of Medicine definition and on additional domains based on the literature. Patient satisfaction was measured with the Medical Outcomes Study 9-item visit rating form. The usual provider continuity (UPC) index was calculated as the proportion of visits to the index physician with relation to all physician visits for the past year by patient report. The CPCI was subjected to item and factor analysis. Scale scores were computed, and the association with patient satisfaction with the visit was tested by correlation.

RESULTS: The factor analysis resulted in four stable and internally consistent factors. The factors were named: interpersonal communication, physician's accumulated knowledge of the patient, coordination of care, and patients' preference to see their regular physician. Each of the CPCI scale scores was significantly associated with patient satisfaction with the visit. The UPC index, length of time as a patient, and intensity of visits were not as strongly associated with the patient satisfaction measure.

CONCLUSIONS: The CPCI provides a brief and reliable measure of four important aspects of the delivery of primary care. The components of primary care are associated with patient satisfaction with visits to family physicians. The CPCI could be used with other outcomes and to assess the effect of interventions and systems changes on the delivery of critical aspects of primary care.