RT Journal Article SR Electronic T1 Follow-up of subjects in prospective studies based in general practice JF The Journal of the Royal College of General Practitioners JO J R Coll Gen Pract FD British Journal of General Practice SP 365 OP 370 VO 34 IS 264 A1 Mary Walker A1 A. G. Shaper YR 1984 UL http://bjgp.org/content/34/264/365.abstract AB In prospective studies of ischaemic heart disease, data on the incidence of morbidity as well as mortality are critical to the understanding of the natural history of disease. In the Regional Heart Study, 7,735 middle-aged men recruited from general practices in 24 towns in England, Wales and Scotland have been examined, and are being followed for morbidity and mortality for at least five years. This paper explains the methods used and the difficulties encountered in maintaining the flow of information on these subjects and, in particular, discusses the problems of removal and tracing. A network of enquiries, using Family Practitioner Committees, the NHS Central Register and the additional 500 doctors (to date) to whom subjects have transferred, has enabled contact to be maintained. In the first seven towns reviewed at five years from the initial examination, replies have been received from 98 per cent of the original sample still alive and living in Great Britain.