The primary observer.

Mortality data served epidemiologists of a past generation well but morbidity data are of greater value. The notification of diseases of 'public health' interest should now be supplemented by the continuing observation of patterns of prevalence and incidence of all diseases. The methods of data recording developed by the Royal College of General Practitioners in the U.K. are ready for further development, making use of the vast information-handling capacity of modern computers. A network of intensively documented observer practices is envisaged, backed by an analytical and co-ordinating centre. The primary observers would be doctors presently engaged in primary health care. The organization and operation of such an epidemiological research network would be expensive. Were resources available the experience of the Research Division of the Royal College of General Practitioners would be invaluable.