Prevention of perinatal transmission of hepatitis b virus: The sensitivity, specificity, and predictive value of the recommended screening questions to detect high-risk women in an obstetric population

McQuillan, G. M. (Dept. of Hospital Epidemiology, Johns Hopkins Hospital, Baltimore, MD 21205), T. R. Townsend, C. B. Johannes, T. Dillard, R. A. Molteni, P. M. Ness, and J. R. Niebyl. Prevention of perinatal transmission of hepatitis B virus: the sensitivity, specificity, and predictive value of the recommended screening questions to detect high-risk women in an obstetric population. Am J Epidemiol 1987; 126:484-91.The Advisory Committee on Immunization Practices recommends that all pregnant women be questioned concerning risk factors for hepatitis B virus infection and that those giving positive responses be serotested. The sensitivity, specificity, and predictive value of those recommended questions among 692 parturient women were determined. A total of 59 currently or previously infected women (hepatitis B surface antigen (HBsAg), antibody to hepatitis B surface antigen (anti-HB5), or antibody to hepatitis B core antigen (anti-HBc) seropositive) were compared with the 633 seronegative women. Among nonwhite women, the sensitivity of a positive response to any one of the recommended questions was 60%. Specificity and positive predictive value were 71% and 19%, respectively. Among white women, the sensitivity, specificity, and positive predictive value were 56%, 75%, and 11%, respectively. To increase such unacceptably low sensitivity, the authors included two additional questions: single marital status and Medicaid/medical assistance payer status. Sensitivity increased to 96% among nonwhite women and 84% among white women. However, a positive response to at least one of the recommended questions or to additional questions was elicited from 78% of all women (92% nonwhite and 64% white). The authors conclude that to prevent perinatal transmission of hepatitis B, we must serotest all women in our obstetric population.