Abstract
This cost-effectiveness study analyzes the cost per quality-adjusted life year (QALY) gained in a randomized controlled trial that tested school support as a structural intervention to prevent HIV risk factors among Zimbabwe orphan girl adolescents. The intervention significantly reduced early marriage, increased years of schooling completed, and increased health-related quality of life. By reducing early marriage, the literature suggests the intervention reduced HIV infection. The intervention yielded an estimated US$1,472 in societal benefits and an estimated gain of 0.36 QALYs per orphan supported. It cost an estimated US$6/QALY gained, about 1 % of annual per capita income in Zimbabwe. That is well below the maximum price that the World Health Organization (WHO) Commission on Macroeconomics and Health recommends paying for health gains in low and middle income countries. About half the girls in the intervention condition were boarded when they reached high school. For non-boarders, the intervention’s financial benefits exceeded its costs, yielding an estimated net cost savings of $502 per pupil. Without boarding, the intervention would yield net savings even if it were 34 % less effective in replication. Boarding was not cost-effective. It cost an additional $1,234 per girl boarded (over the 3 years of the study, discounted to present value at a 3 % discount rate) but had no effect on any of the outcome measures relative to girls in the treatment group who did not board. For girls who did not board, the average cost of approximately 3 years of school support was US$973.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
Notes
To analyze cost-effectiveness for all girls assisted, using simulation runs to estimate mean cost/QALY gained and its standard error is not valid. When the intervention offers net cost savings, the more QALYs gained, the higher (closer to zero) its cost per QALY gained will become (e.g., -$300/.4 = -$750 is smaller than -$300/.6 = -$500). Conversely, if the intervention does not offer net cost savings, the more QALYs gained, the lower the cost/QALY gained e.g., $300/.4 = $750 is larger than $300/.6 = $500). The mean is not a sound measure because of the conflicting meanings of large positive and negative numbers. Furthermore, as the number of QALYs gained becomes smaller than ±0.03 (almost a certainty for a few cases in a probabilistic simulation with 1 million replicates), the cost/QALY becomes huge, skewing the mean.
References
Badri, M., Cleary, S., Maartens, G., Pitt, J., Bekker, L. G., Orrell, C., & Wood, R. (2006). When to initiate highly active antiretroviral therapy in sub-Saharan Africa? A South African cost-effectiveness study. Antiviral Therapy, 11, 63–72.
Baird, S., Chirwa, E., McIntosh, C., & Ozler, B. (2010). The short-term impacts of a schooling conditional cash transfer program on the sexual behavior of young women. Health Economics, 19, 55–68. doi:10.1002/hec.1569.
Beck, E. J., Harling, G., Gerbase, S., & DeLay, P. (2010). The cost of treatment and care for people living with HIV infection: Implications of published studies, 1999-2008. Current Opinion in HIV and AIDS, 5, 215–224. doi:10.1097/COH.0b013e32833860e9.
Bennell, P., & Malaba, J. (1993). Up-dating rates of return to education: Zimbabwe in the late 1980s. International Journal of Educational Development, 13, 277–287.
Birdthistle, I. J., Floyd, S., Machingura, A., Mudziwapasi, N., Gregson, S., & Glynn, J. R. (2008). From affected to infected? Orphanhood and HIV risk among female adolescents in urban Zimbabwe. AIDS, 22, 759–766. doi:10.1097/QAD.0b013e3282f4cac7.
Catalano, R. F., & Hawkins, J. D. (1996). The social development model: A theory of antisocial behavior. In J. D. Hawkins (Ed.), Delinquency and crime: Current theories (pp. 149–197). New York: Cambridge University Press.
Central Statistical Office (CSO) [Zimbabwe], & Macro International Inc. (2007). Zimbabwe demographic and health survey, 2005-2006. Calverton: Central Statistical Office and Macro International, Inc.
Cheng, A. K., Rubin, H. R., Powe, N. R., Mellon, N. K., Francis, H. W., & Niparko, J. K. (2000). Cost-utility analysis of the cochlear implant in children. Journal of the American Medical Association, 284, 850–856. doi:10.1001/jama.284.7.850.
Cho, H., Hallfors, D. D., Mbai, I. I., Itindi, J., Milimo, B. W., Halpern, C. T., & Iritani, B. J. (2011). Keeping adolescent orphans in school as HIV prevention: Evidence from a randomized controlled trial in Kenya. Journal of Adolescent Health, 48, 523–526. doi:10.1016/j.jadohealth.2010.08.007.
Clement, F. M., Harris, A., Li, J. J., Yong, K., Lee, K. M., & Manns, B. J. (2009). Using effectiveness and cost-effectiveness to make drug coverage decisions: A comparison of Britain, Australia, and Canada. Journal of the American Medical Association, 302, 1437–1443. doi:10.1001/jama.2009.1409.
Cowan, F. M., Pascoe, S. J. S., Langhaug, L. F., Dirawo, J., Chidiya, S., Jaffar, S., Mbizvo, M., Stephenson, J. M., Johnson, A. M., Power, R. M., Woelk, G., & Hayes, R. J. (2008). The Regai Dzive Shiri Project: A cluster randomised controlled trial to determine the effectiveness of a multi-component community-based HIV prevention intervention for rural youth in Zimbabwe - study design and baseline results. Tropical Medicine & International Health, 13, 1235–1244. doi:TMI2137 [pii] 10.1111/j.1365-3156.2008.02137.x.
Creese, A., Floyd, K., Alban, A., & Guinness, L. (2002). Cost-effectiveness of HIV/AIDS interventions in Africa: A systematic review of the evidence. Lancet, 359, 1635–1643.
Duflo, E., Dupas, P., Kremer, M., & Sinei, S. (2006). Education and HIV/AIDS prevention: Evidence from a randomized evaluation in Western Kenya. World Bank Policy Research working paper 4024, background paper to the 2007 World Development Report.
Drummond, M. F., Sculpher, M. J., Torrance, G. W., O’Brien, B. J., & Stoddart, G. L. (2005). Methods for the economic evaluation of health care programmes (3rd ed.). New York: Oxford University Press.
Frick, K. D., Carlson, M. C., Glass, T. A., McGill, S., Rebok, G. W., Simpson, C., & Fried, L. P. (2004). Modeled cost-effectiveness of the Experience Corps Baltimore based on a pilot randomized trial. Journal of Urban Health, 81, 106–117. doi:10.1093/jurban/jth097.
Galarraga, O., Colchero, M. A., Wamai, R. G., & Bertozzi, S. M. (2009). HIV prevention cost-effectiveness: A systematic review. BMC Public Health, 9 Supplement 1, S5. doi: 1471-2458-9-S1-S5 10.1186/1471-2458-9-S1-S5.
Gold, M. R., Siegel, J. E., Russell, L. B., & Weinstein, M. C. (Eds.). (1996). Cost-effectiveness in health and medicine: Report of the panel on cost-effectiveness in health and medicine. New York: Oxford University Press.
Gregson, S., Nyamukapa, C. A., Garnett, G. P., Wambe, M., Lewis, J. J. C., Mason, P. R., Chandiwana, S. K., & Anderson, R. M. (2005). HIV infection and reproductive health in teenage women orphaned and made vulnerable by AIDS in Zimbabwe. AIDS Care, 17, 785–794. doi:10.1080/09540120500258029.
Gupta, G. R., Parkhurst, J. O., Ogden, J. A., Aggleton, P., & Mahal, A. (2008). Structural approaches to HIV prevention. Lancet, 372, 764–775. doi:10.1016/S0140-6736(08)608879.
Haddix, A. C., Teutsch, S. M., & Corso, P. S. (2003). Prevention effectiveness: A guide to decision analysis and economic evaluation. New York: Oxford University Press.
Hallfors, D., Cho, H., Rusakaniko, S., Iritani, B. J., Mapfumo, J., & Halpern, C. T. (2011). Supporting adolescent orphan girls to stay in school as HIV risk prevention: Evidence from a randomized controlled trial in Zimbabwe. American Journal of Public Health, 101, 1082–1088. doi:10.2105/AJPH.2010.300042.
Hallfors, D. D., Iritani, B., Miller, W. C., & Bauer, D. (2007). Sexual and drug behavior patterns and HIV/STD racial disparities: The need for new directions. American Journal of Public Health, 97, 125–132. doi:10.2105/AJPH.2005.075747.
Jelsma, J., Hansen, K., De Weerdt, W., De Cock, P., & Kind, P. (2003). How do Zimbabweans value health states? Population Health Metrics, 1, 11.
Jessor, R., Turbin, M. S., & Costa, F. (1998). Risk and protection in successful outcomes among disadvantaged adolescents. Applied Development Science, 2, 194–208.
Khumalo-Sakutukwa, G., Morin, S. F., Fritz, K., Charlebois, E. D., Rooyen, H., Chingono, A., Modiba, P., Mrumbi, K., Visrutaratna, S., Singh, B., Sweat, M., Celentano, D. D., Coates, T. J., & NIMH Project Accept Study Team. (2008). Project Accept (HPTN 043): A community-based intervention to reduce HIV incidence in populations at risk for HIV in Sub-Saharan Africa and Thailand. Journal of Acquired Immune Deficiency Syndromes, 49, 422–431. doi:10.1097/QAI.0b013e31818a6cb5.
Kirby, D. (1999). Looking for reasons why: The antecedents of adolescent sexual risk taking, pregnancy and childbearing. Washington, DC: National Campaign to Prevent Teen Pregnancy.
Murray, C. J. L., & Lopez, A. D. (Eds.). (1996). The global burden of disease. Volume 1 of the global burden of disease and injury series. Cambridge, MA: Harvard University Press.
Polinder, S., van Beeck, E.F., Essink-Bot, M.L., Toet, H., Looman, C.W., Mulder, S., & Meerding, W.J. (2007). Functional outcome at 2.5, 5, 9, and 24 months after injury in the Netherlands. Journal of Trauma, 62, 133-141. doi:10.1097/TA.0b013e31802b71c9.
Resnick, M. D., Bearman, P. S., Blum, R. W., Bauman, K. E., Harris, K. M., Jones, J., Tabor, J., Beuhring, T., Sieving, R. E., Shew, M., Ireland, M., Bearinger, L. H., & Udry, J. R. (1997). Protecting adolescents from harm: Findings from the National Longitudinal Study on Adolescent Health. Journal of the American Medical Association, 278, 823–832. doi:10.1001/jama.1997.03550100049038.
Thurman, T. R., Brown, L., Richter, L., Maharaj, P., & Magnani, R. (2006). Sexual risk behavior among South African adolescents: Is orphan status a factor? AIDS and Behavior, 10, 627–635. doi:10.1007/s10461-006-9104-8.
Tongsiri, S., & Cairns, J. (2011). Estimating population-based values for EQ-5D health states in Thailand. Value in Health, published on-line in advance of print. doi: 10.1016/j.jval.2011.06.005.
WHO Commission on Macroeconomics and Health. (2001). Macroeconomics and health: Investing in health for economic development. Geneva: World Health Organization.
World Bank. (2011). WorldDataBank, world development indicators and global development finance. Accessed July 19, 2011, at: http://databank.worldbank.org/ddp/home.do?CNO=2&Step=12&id=4.
Acknowledgement
This project was supported by Grant R01HD055838 (Denise Hallfors, P.I.) from the Eunice Kennedy Shriver National Institute of Child Health & Human Development (NICHD). The content is solely the responsibility of the authors and does not necessarily represent the official views of NICHD or the National Institutes of Health. We are deeply grateful to the participating schools, headmasters, teachers, helpers, and students. We also thank Witness Chekumunyara who compiled all cost data for our study; Bonita Iritani who managed the participant data base; Shane Hartman who managed the cost data base and coordinated final manuscript production; and data collection contributions of the Zimbabwean research staff.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Miller, T., Hallfors, D., Cho, H. et al. Cost-Effectiveness of School Support for Orphan Girls to Prevent HIV Infection in Zimbabwe. Prev Sci 14, 503–512 (2013). https://doi.org/10.1007/s11121-012-0315-0
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11121-012-0315-0