A study by the Rand Corp. suggests that high managed care penetration in urban areas is forcing a slow but tangible physician migration to the country — away from HMOs.

Rand followed 75,000 doctors who finished graduate medical education between 1989 and 1994. Early in the period, primary care physicians tended to settle in metropolitan areas, but specialists were more apt to practice in places with low managed care penetration. Toward the end of the study period, however, new primary care doctors were also less likely than they had been to settle in high-penetration markets.

The results were published in the November issue of the journal Medical Care.