The Cost-effectiveness of Voluntary Counseling and Testing of Hospital Inpatients for HIV Infection

OBJECTIVE: To evaluate the cost-effectiveness of voluntary counseling and testing of US hospital inpatients for the human immunodeficiency virus (HIV). DATA SOURCES: Data for entry into the model were derived from a review of the literature, consultation with experts, and consensus of the authors. DATA EXTRACTION: We rated our confidence in these probabilities and costs by grading the data inputs using methods adapted from those of the US Preventive Services Task Force. DATA SYNTHESIS: Decision analysis models were developed to evaluate two outcomes: (1) cost per health care worker (HCW) HIV infection averted if measures are taken by the HCW to reduce his or her risk of acquiring HIV; and (2) cost per inpatient HIV infection detected. Sensitivity analyses were also conducted. Using baseline input values, testing to avert HCW infection may prevent 3.6 HIV infections per year at a total program cost of $2.7 billion, or a cost of $753 million per infection averted. At baseline assumptions (seroprevalence = 1%), testing to detect inpatient HIV infection would cost $16,104 per year per infection detected. Cost-effectiveness at baseline drops to $8353 per HIV infection detected if the seroprevalence is 10%. If testing is limited to hospitals with inpatient seroprevalences of at least 1%, approximately 5400 persons per year will be falsely labeled HIV-positive. CONCLUSIONS: This analysis provides no justification for testing inpatients to prevent HIV infection of HCWs. Screening inpatients to detect HIV infection may be justified at seroprevalences exceeding 1%, but issues of medical or social discrimination, false-positive results, informed consent, and logistics must be resolved first.