Use of epidemiology in clinical medical publications, 1983-1999: a citation analysis.

Epidemiologists respond to the information needs of health professionals. Although medical professionals are routine users of epidemiologic information, use within medical specialties varies remarkably. To explore the variation in use of epidemiologic information across clinical medical specialties, the authors examined the scientific literature by analyzing patterns of citation of specific journal articles to and by the American Journal of Epidemiology (AJE). A total of 178,396 journal citations to and 126,478 citations by AJE were made from 1983 through 1999; citations were classified according to the subject category of the referencing or referenced journal. Clinical medical journals accounted for 50.6% of all citations combined (both referenced to and referenced by AJE); general/internal medicine (17.9%), cancer (10.4%), and cardiovascular (4.9%) journals had the highest number of citations. Few citations to and by AJE were found in publications specializing in dermatology, gastroenterology, orthopedics, allergy, anesthesiology, surgery, rheumatology, and other areas. Trend patterns of citations between clinical and epidemiologic literature indicated that citations to the fields of cardiovascular disease and cancer are increasing, whereas citations regarding pediatrics have remained stable. This analysis suggests an increasing interchange of information between epidemiologists and clinicians specializing in certain fields, uncovering potential research opportunities for epidemiologists.