BMC Public Health 2009, 9:310 http://www.biomedcentral.com/1471-2458/9/310 graphic prevalence patterns and indications of trends among childbearing women. AIDS 1997, 11:339-345. 18. UNAIDS: Report on the global HIV/AIDS epidemic. Geneva, Switzerland; 1998. 19. Fylkesnes K, Musonda RM, Sichone M, Ndhlovu Z, Monze M, Tembo F, Phiri S, Malamba C: Declining HIV prevalence and risk behav- iours in Zambia: evidence from surveillance and population- based surveys. AIDS 2001, 15:907-916. 20. Kilian AH, Gregson S, Ndyanabangi B, Walusaga K, Kipp W: Reduc- tion in risk behaviour provide the most consistent explana- tion for declining HIV-1 prevalence in Uganda. AIDS 1999, 13(3):391-398. 21. de Walque D, Nakiyingi-Miiro JS, Busingye J, Whitworth JA: Chang- ing association between schooling levels and HIV-1 infection over 11 years in a rural population cohort in south-west Uganda. Trop Med Int Health 2005, 10(10):993-1001. 22. Michelo C, Sandøy IF, Fylkesnes K: Marked HIV prevalence declines in higher educated young people: evidence from population-based surveys (1995 – 2003) in Zambia. AIDS 2006, 20(7):1031-1038. 23. Michelo C, Sandøy IF, Dzekedzeke K, Siziya S, Fylkesnes K: Steep HIV prevalence declines among young people in selected Zambian communities: population-based observation (1995 – 2003). BMC Public Health 2006, 6(279):. 24. Vandemoortele J, Delamonica E: The education vaccine against HIV. Issues in Comparative Education 2002, 3(1):6-13. 25. Sandøy IF, Michelo C, Siziya S, Fylkesnes K: Associations between sexual behaviour change in young people and decline in HIV prevalence in Zambia. BMC Public Health 2007, 7:60. 26. Boerma JT, Weir SS: Integrating demographic and epidemio- logical approaches to research on HIV/AIDS: the proximate- determinants framework. J Infect Dis 2005, 191(Suppl 1):S61-67. 27. Guy LL, Giguere G: Formatting data files for repeated-meas- ures analyses in SPSS: using the aggregate and restructure procedures. Tutorial in Quantitative Methods for Psychology 2006, 2(1):20-25. 28. Hargreaves RJ, Bonell CP, Boler T, Boccia D, Birdthistle I, Fletcher A, Pronyk PM, Glynn JR: Systematic review exploring time trends in the association between educational attainment and risk of HIV infection in sub-Saharan africa. AIDS 2008, 22:403-414. 29. Rutstein OS, Kiersten J: The DHS wealth index: DHS compara- tive reports no. 6. Calverton: ORC Macro; 2004. 30. Jesus R-V, Zimmerman MA, Newcomb MD: Sexual risk behaviour among youth: modelling the influence of pro-social activities and socioeconomic factors. J Health Soc Behav 1998, 39:237-253. 31. Bingham RC, Crockett LJ: Longitudinal adjustment patterns of boys and girls experiencing early, middle and late sexual intercourse. Dev Psychology 1996, 36:647-658. 32. Merson HM, O' Malley J, Serwadda D, Apisuk C: The history and challenge of HIV prevention. The Lancet – HIV prevention 2008, Series:7-20. 33. Gupta GR, Parkhurst JO, Ogden JA, Aggleton P, Mahal A: Structural approaches to HIV prevention. The Lancet – HIV prevention 2008, Series:52-63. 34. Krueger LE, Wood RW, Diehr P, Maxwell CL: Poverty and HIV seropositivity: the poor are more likely to be infected. AIDS 1990, 4(8):811-814. 35. von Luger L: HIV/AIDS prevention and class and socio-eco- nomic related factors of risk of HIV Infection. London: Impe- rial College, London, UK; 1998. 36. Rogers E: Diffusion of innovation. 5th edition. New York: Free Press; 2003. 37. Mitchell C, Marilyn B, Chilangwa B, Maimbolwa-Sinyangwe IM: Girls' education in Zambia: everyone's responsibility – a policy framework for participatory process. Int Review of Education 1999, 45(5/6):417-430. 38. CSO: 2000 census of population and housing report. 2000 [http://www.zamstats.gov.zm/census.php]. Lusaka: Central Statistical Office – Zambia 39. CSO: Living conditions monitoring survey report. Lusaka: Central Statistical Office-Zambia; 2004. 40. Browne WJ: Sample sizes for multilevel models. In Centre for Multilevel Modelling Volume 2008. London: University of Bristol; 2008. 41. Glynn JR, Carael M, Auvert B, Kahindo M, Chege J, Musonda R, Kaona F, Buve A: Why do young women have a much higher preva- lence of HIV than young men? A study in Kisumu, Kenya and Ndola, Zambia. AIDS 2001, 15(Suppl 4):S51-60. 42. Buve A, Lagarde E, Carael M, Rutenberg N, Ferry B, Glynn JR, Laourou M, Akam E, Chege J, Sukwa T: Interpreting sexual behav- iour data: validity issues in the multicentre study on factors determining the differential spread of HIV in four African cit- ies. AIDS 2001, 15(Suppl 4):S117-126. 43. Gregson S, Nyamukapa C, Garnett G, Mason P, Zhumau T, Carael M, Chandiwana S, Anderson R: Sexual mixing patterns and sex-dif- ferentials in teenage exposure to HIV infection in rural Zim- babwe. Lancet 2002, 359:1896-1903. 44. Hewett P, Mensch B, Erulkar A: Consistency in the reporting of sexual behaviour by adolescent girls in Kenya: a comparison of interviewing methods. Sex Transm Infect 2004, 80(Suppl 2):8. 45. Buckner B, Singh K, Tate J: Zambia sexual behaviour survey 2005. In ZSBS 2005 Report Edited by: Buckner B, Singh K, Tate J. Lusaka and Maryland: Central Statistical Office, Ministry of Health, MEASURE Evaluation; 2006. Pre-publication history The pre-publication history for this paper can be accessed here: http://www.biomedcentral.com/1471-2458/9/310/pre pub Publish with Bio Med Central and every scientist can read your work free of charge "BioMed Central will be the most significant development for disseminating the results of biomedical research in our lifetime." 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