The role of epidemiology in planning and evaluation. The British approach.

Epidemiological knowledge is essential to provide sound advice on the provision of health services. The role of the community physician in the UK can only be understood with reference to the structure of the National Health Service. His function at District level is illustrated by strategies of secondary prevention such as anti-smoking campaigns in the fight against cardio-respiratory disease, and the detection of hypertensives in out-patient departments. At national level decisions mainly concern priority. The need for reliable evaluative research to be done before policy decisions are made is evident from several studies undertaken at St. Thomas' Hospital, London, and to achieve this epidemiologists, planners and administrators must work closely together.