Physician-delivered births in Washington State, 1978: geographic patterns.

Linkage of birth certificate and physician survey data was used to analyze characteristics of physicians attending deliveries in Washington State in 1978. This analysis revealed substantial differences in attendant characteristics between rural and urban areas. The more urban areas were characterized by a higher proportion of births delivered by obstetrical specialists and a higher average number of births/physician. These results are briefly discussed in terms of supply and accessibility of physicians in several different rural-urban classifications.