Effect of periodic vitamin A supplementation on mortality and morbidity of human immunodeficiency virus-infected children in Uganda: a controlled clinical trial [corrected] [published erratum appears in NUTRITION 2005 Feb;21(2):287]. - Semba RD; Ndugwa C; Perry RT; Clark TD; Jackson JB; Melikian G; Tielsch J; Mmiro F (Nutrition, 2005)