Medical Practice Medicine and Books Br Med J (Clin Res Ed) 1987; 295 doi: https://doi.org/10.1136/bmj.295.6611.1479 (Published 05 December 1987) Cite this as: Br Med J (Clin Res Ed) 1987;295:1479 Article Related content Metrics Responses Peer review Related articles No related articles found.