editorial board EDITOR IN CHIEF Professor G I Muguti ASSOCIATE EDITORS Professor IT Gangaidzo Dr S P Munjanja EDITORIAL BOARD MEMBERS Professor MM Chidzonga Professor P Jacobs D.rRA Kambarami Professor A S Latif Professor P R Mason Professor CT Musabayane Professor KJ Nathoo Mr L Nystrom Dr S Siziya (Zimbabwe) (South Africa) (Zimbabwe) (Zimbabwe) (Zimbabwe) (Zimbabwe) (Zimbabwe) (Sweden) (Zambia) PAST EDITORS Professor Gelfand (1953-1985) Professor H M Chinyanga (1985-1990) Professor J A Matenga (1991-1999) ADMINSTRATIVE AND OFFICE STAFF Director o f Publications: Mr Munani S Mtetwa Administrative Manager: Mr Christopher Mashavira Technical Editor: Mrs Ling M Cooper Statistical A ch’isor: Mr S Rusakaniko Secretary: Ms Perpetua Manuwa All manuscripts will be prepared with the International Committee of Medical Journal Editors - Uniform requirements for manuscripts submitted to Biomedical Journals, 1993. Manuscripts submitted for publication are accepted on the understanding that they are contributed exclusively to The Central African Journal o fMedicine. A statement to that effect should be included in the letter accompanying the manuscript. Communications concerning editorial matter, advertising, subscriptions, change of address, etc. Should be addressed to the Administrative Manager, P. O. Box A195 Avondale, Harare, Zimbabwe. The subscription rate for surface transmission including postage for year 2001 is Z$770.00 locally; Africa US$160.00 for individuals and US$215.00 for institutions; and US$210.00 for individuals and US$230.00 for institutions for the rest of the world per annum. The subscription rate for airmail transmission for year 2001 in Africa is US$275.00 for individuals US$290.00 for institutions and US$70.00 for postage; and US$300.00 for individuals US$320.00 for institutions and US$70.00 for postage for the rest of the world per annum. Owned and published by the Central African Journal of Medicine in conjuction with the Faculty of Medicine University of Zimbabwe STRAND MULTIPRINT (pvt) ltd