Diagnostic radiology usage in ambulatory and hospital care

Data from a nationwide survey of physicians show that there were a total of 214 million medical radiologic examinations performed in the United States in 1977, or just under one for each member of the resident population. Approximately 58% of these procedures were performed in ambulatory patients (including those in hospital outpatient departments) and 42% were in hospitalized patients. Data for the number of visits with (single or multiple) radiologic examinations produced an estimate of 184 million annual visits with one or more diagnostic radiographs. These estimates provide a comprehensive measure of national use of diagnostic radiology at the time the data were collected, as well as a basis of comparison for analyses of contemporary patterns of utilization of radiologic procedures.