The Michigan Ambulatory Medical Care Survey: results and utility relative to the National Survey.

Percentage distributions for variables in the Michigan Ambulatory Medical Care Survey (MAMCS), both for the Detroit Standard Metropolitan Statistical Area (SMSA) and the State as a whole, are compared with those from the National Ambulatory Medical Care Survey (NAMCS). The MAMCS data are a subset of the NAMCS data, since the MAMCS was carried out by augmenting the NAMCS in Michigan. Differences in the impact of survey results for the three areas are examined in the context of planning and developing ambulatory health care services. A specific application of survey data is examined, namely, its use in planning the Health Care Institute of Wayne State University and the Detroit Medical Center. The survey results for the three areas are similar enough to warrant the use of data from the national survey in the planning and evaluation of health services locally, although special studies of a few items such as X-ray usage may be needed. To reestablish local credibility for national results, or to detect changes in patterns which may develop, another Statelevel survey is suggested at the time of a census. Based on the experience with the MAMCS, augmentation of the NAMCS or other national surveys would be used in other States.

Evaluation and application of continuity measures in primary care settings.

Continuity of contact between patients and physicians has become an important criterion of quality primary care. Using three measures of continuity that have appeared in the literature, this article examines, through the use of simulated data and through application to data from five primary care settings, the differences and utility of these approaches for measuring continuity. Further, these measures are applied to four selected diagnoses from each of the five sites, and the observed continuity scores afforded patients with these diagnoses are compared with those expected based on the population. Finally, the scores are correlated with the number of return visits prescribed and kept and with the rate at which laboratory studies are ordered. The findings indicate that site-specific differences in continuity prevail even after adjustments in the number of visits. Continuity based on selected diagnoses is greater, for the most part, than continuity afforded the patient population. Finally, continuity is related to the number of return visits prescribed but not to the number kept or the rate at which laboratory studies are ordered. The implications of continuity for other aspects of quality patient care are discussed.