Hetherington et al examine the differences between provider-sponsored plans, commercial carriers, and prepaid group-practice plans in southern California, basing their work on data collected from six plans in Los Angeles County, from 1965 to 1971. Information was gathered from the health insurance agencies, subscribers to each plan, and physicians who served the subscribers. Performance of the plans was measured according to amounts of medical service used, aspects of quality of those services, consumer expenditures, and consumer satisfaction.
There were lower hospitalization rates in the large group-practice plans. Group plans tended to provide more preventive services and do more laboratory and radiology testing, but physicians in the large group plan "do not make note of the results as frequently as their colleagues in private practice." The hospital-sponsored plan had the highest rate of continuity of care. Families in the large group-practice plan had significantly lower out-of-pocket expenses per person while the