title: A statistical view of clinical trials in chronic hepatitis B.
abstract: From a review of thirty published papers it is clear that the variety of options for treatment of hepatitis B have led to a large number of small exploratory trials. However, small groups lead to imprecise estimates of seroconversion rates; for example a result of 4/10 gives an estimate of 40% with 80% confidence limits of 20% and 60%. A number of possible prognostic factors have been proposed and, whilst their importance is generally unproven, their estimated effects are considerable. Comparison between studies can therefore be misleading; for example comparing two treatments A and B of identical efficacy in two common populations could give a 1 in 4 chance of declaring B to give double the seroconversion rate of A. Larger, randomised, controlled trials on homogeneous patient groups are needed to give conclusive evidence of the efficacy or otherwise of various treatment regimes.
mesh_terms: D002986:Clinical Trials as Topic; D006509:Hepatitis B / Q000628:therapy*; D006521:Hepatitis, Chronic / Q000628:therapy*; D006801:Humans; D011379:Prognosis; D012107:Research Design; D013223:Statistics as Topic; D014740:Vidarabine / Q000627:therapeutic use; D001084:Vidarabine Phosphate / Q000627:therapeutic use
chemical_list: D001084:Vidarabine Phosphate; D014740:Vidarabine