Giles Reid1, Andrew C Voetsch2, Paul Stupp2, Stephen McCracken2, Graham Kalton3, Sindisiwe Dlamini4, James McOllogi Juma5, Thoko Kalua6, Wilford Kirungi7, Masebeo Koto8, Owen Mugurungi9, Lloyd Mulenga10, Nicholus Mutenda11, Lawrence Marum2, Suzue Saito1. 1. ICAP at Columbia University, New York, NY. 2. U.S. Centers for Disease Control and Prevention, Atlanta, GA. 3. Westat, Rockville, MD. 4. Ministry of Health, Eswatini, Mbabane, Eswatini. 5. Ministry of Health, Community Development, Gender, Elderly and Children, Tanzania, Dodoma, Tanzania. 6. Ministry of Health and Population, Lilongwe, Malawi. 7. Ministry of Health, Republic of Uganda, Kampala, Uganda. 8. Ministry of Health, Lesotho, Maseru, Lesotho. 9. Ministry of Health and Child Care, Harare, Zimbabwe. 10. Ministry of Health, Lusaka, Zambia; and. 11. Ministry of Health and Social Services, Windhoek, Namibia.
Abstract
BACKGROUND: Measurement of mother-to-child HIV transmission through population-based surveys requires large sample sizes because of low HIV prevalence among children. We estimate potential improvements in sampling efficiency resulting from a targeted sample design. SETTING: Eight countries in sub-Saharan Africa with completed Population-based HIV Impact Assessment (PHIA) surveys as of 2017. METHODS: The PHIA surveys used a geographically stratified 2-stage sample design with households sampled from randomly selected census enumeration areas. Children (0-14 years of age) were eligible for HIV testing within a random subsample of households (usually 50%). Estimates of child HIV prevalence in each country were calculated using jackknife replicate weights. We compared sample sizes and precision achieved using this design with a 2-phase disproportionate sample design applied to strata defined by maternal HIV status and mortality. RESULTS: HIV prevalence among children ranged from 0.4% (95% confidence interval: 0.2 to 0.6) in Tanzania to 2.8% (95% confidence interval: 2.2 to 3.4) in Eswatini with achieved relative standard errors between 11% and 21%. The expected precision improved in the targeted design in all countries included in the analysis, with proportionate reductions in mean squared error ranging from 27% in Eswatini to 61% in Tanzania, assuming an equal sample size. CONCLUSIONS: Population-based surveys of adult HIV prevalence that also measure child HIV prevalence should consider targeted sampling of children to reduce required sample size, increase precision, and increase the number of positive children tested. The findings from the PHIA surveys can be used as baseline data for informing future sample designs.
BACKGROUND: Measurement of mother-to-child HIV transmission through population-based surveys requires large sample sizes because of low HIV prevalence among children. We estimate potential improvements in sampling efficiency resulting from a targeted sample design. SETTING: Eight countries in sub-Saharan Africa with completed Population-based HIV Impact Assessment (PHIA) surveys as of 2017. METHODS: The PHIA surveys used a geographically stratified 2-stage sample design with households sampled from randomly selected census enumeration areas. Children (0-14 years of age) were eligible for HIV testing within a random subsample of households (usually 50%). Estimates of child HIV prevalence in each country were calculated using jackknife replicate weights. We compared sample sizes and precision achieved using this design with a 2-phase disproportionate sample design applied to strata defined by maternal HIV status and mortality. RESULTS: HIV prevalence among children ranged from 0.4% (95% confidence interval: 0.2 to 0.6) in Tanzania to 2.8% (95% confidence interval: 2.2 to 3.4) in Eswatini with achieved relative standard errors between 11% and 21%. The expected precision improved in the targeted design in all countries included in the analysis, with proportionate reductions in mean squared error ranging from 27% in Eswatini to 61% in Tanzania, assuming an equal sample size. CONCLUSIONS: Population-based surveys of adult HIV prevalence that also measure child HIV prevalence should consider targeted sampling of children to reduce required sample size, increase precision, and increase the number of positive children tested. The findings from the PHIA surveys can be used as baseline data for informing future sample designs.
Authors: Kristin Brown; Daniel B Williams; Steve Kinchen; Suzue Saito; Elizabeth Radin; Hetal Patel; Andrea Low; Stephen Delgado; Owen Mugurungi; Godfrey Musuka; Beth A Tippett Barr; E Amaka Nwankwo-Igomu; Leala Ruangtragool; Avi J Hakim; Thokozani Kalua; Rose Nyirenda; Gertrude Chipungu; Andrew Auld; Evelyn Kim; Danielle Payne; Nellie Wadonda-Kabondo; Christine West; Elizabeth Brennan; Beth Deutsch; Anteneh Worku; Sasi Jonnalagadda; Lloyd B Mulenga; Kumbutso Dzekedzeke; Danielle T Barradas; Haotian Cai; Sundeep Gupta; Stanley Kamocha; Margaret A Riggs; Karampreet Sachathep; Wilford Kirungi; Joshua Musinguzi; Alex Opio; Sam Biraro; Elizabeth Bancroft; Jennifer Galbraith; Herbert Kiyingi; Mansoor Farahani; Wolfgang Hladik; Edith Nyangoma; Choice Ginindza; Zandile Masangane; Fortune Mhlanga; Zandile Mnisi; Pasipamire Munyaradzi; Amos Zwane; Sean Burke; Felix B Kayigamba; Harriet Nuwagaba-Biribonwoha; Ruben Sahabo; Trong T Ao; Chiara Draghi; Caroline Ryan; Neena M Philip; Fausta Mosha; Aroldia Mulokozi; Phausta Ntigiti; Angela A Ramadhani; Geoffrey R Somi; Cecilia Makafu; Veronicah Mugisha; Julius Zelothe; Kayla Lavilla; David W Lowrance; Rennatus Mdodo; Elizabeth Gummerson; Paul Stupp; Kyaw Thin; Koen Frederix; Stefania Davia; Amee M Schwitters; Stephen D McCracken; Yen T Duong; David Hoos; Bharat Parekh; Jessica E Justman; Andrew C Voetsch Journal: MMWR Morb Mortal Wkly Rep Date: 2018-01-12 Impact factor: 17.586
Authors: Mary Mahy; Martina Penazzato; Andrea Ciaranello; Lynne Mofenson; Constantin T Yianoutsos; Mary-Ann Davies; John Stover Journal: AIDS Date: 2017-04 Impact factor: 4.177