Schrappe M, Lauterbach K
Quality Management Program, University Hospital of Cologne, Germany.
AIDS. 1998;12 Suppl A:S231-8.
Systematic review on cost-effectiveness of public health interventions for primary HIV-prevention programs.
Rating of publications using the guidelines for economic studies in medicine of the British Medical Journal Economic Evaluation Working Party.
Studies with defined nondrug intervention, defined study population, identifiable method of analysis and at least one endpoint for evaluation of intervention were included. One publication could consist of more than one study. Methods to generate effectiveness data, inclusion of human costs and kind of outcome parameters for economic evaluation were documented. To avoid bias in performing the review, the British Medical Journal guidelines were applied. Cost-effectiveness data were reviewed according to outcome parameters used in economic evaluation.
Forty studies were identified in 34 publications, 30/40 from the United States and 22 supported by public funding; only five studies were directed to men who have sex with men, intravenous drug users and persons with HIV-infected partners. Screening programs and counseling with testing accounted for 30/40 studies. Complete research question (intervention and outcome) was presented in 29/40 studies (72.5%). Thirty-four studies were conducted from the societal perspective and the viewpoint was clearly stated in 31/40 studies. Incremental analysis was performed in 21 studies, correction for inflation in two and discounting when appropriate in 23/29 studies; sensitivity analysis was performed in 23/40. Effectiveness data were presented in 38 studies. Diagnosis of previously unknown HIV infection (n = 11), sexual (n = 7) and vertical transmission (n = 6), infection of patients by healthcare workers and life years saved (both n = 6) served as the most common outcome parameters. In 21 studies, human costs were included in the estimation of costs (52.5%) and nine studies used the human capital approach. Cost-effectiveness data revealed costs between US$460 and US$1.2 million per case of previously unknown HIV infection prevented, strongly depending on prevalence. Studies on sexual and vertical transmission demonstrated lower costs when the benefits of treatment were included. Costs for 1 life-year saved varied between $29,000 and $458,000.
The British Medical Journal guidelines for economic analysis in medicine are a feasible instrument for systematic reviews of cost-effectiveness studies on primary HIV infection. The quality of published studies varies widely. A clear definition of outcome parameters as an object of economic evaluation can be regarded as crucial, besides incremental analysis, discounting, and inclusion of human costs. Further work is needed to develop and evaluate a specific rating system for cost-effectiveness analysis in this field.
