Medicine and the MediaBr Med J (Clin Res Ed) 1982; 285 doi: https://doi.org/10.1136/bmj.285.6335.129 (Published 10 July 1982) Cite this as: Br Med J (Clin Res Ed) 1982;285:129
Log in using your username and password
Log in through your institution
Register for a free trial to thebmj.com to receive unlimited access to all content on thebmj.com for 14 days.
Sign up for a free trial