Performance of verbal autopsy methods in estimating HIV-associated mortality among adults in South Africa

Aaron S Karat; Noriah Maraba; Mpho Tlali; Salome Charalambous; Violet N Chihota; Gavin J Churchyard; Katherine L Fielding; Yasmeen Hanifa; Suzanne Johnson; Kerrigan M McCarthy; Kathleen Kahn; Daniel Chandramohan; Alison D Grant

doi:10.1136/bmjgh-2018-000833

Performance of verbal autopsy methods in estimating HIV-associated mortality among adults in South Africa

BMJ Glob Health. 2018 Jul 3;3(4):e000833. doi: 10.1136/bmjgh-2018-000833. eCollection 2018.

Authors

Aaron S Karat¹, Noriah Maraba², Mpho Tlali², Salome Charalambous^{2

3}, Violet N Chihota^{2

3}, Gavin J Churchyard^{1

2

3}, Katherine L Fielding^{1

3}, Yasmeen Hanifa¹, Suzanne Johnson⁴, Kerrigan M McCarthy^{2

5}, Kathleen Kahn^{6

7

8}, Daniel Chandramohan⁹, Alison D Grant^{1

3

10

11}

Affiliations

¹ TB Centre, London School of Hygiene & Tropical Medicine, London, UK.
² The Aurum Institute, Johannesburg, South Africa.
³ School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
⁴ Foundation for Professional Development, Pretoria, South Africa.
⁵ Division of Public Health, Surveillance and Response, National Institute for Communicable Diseases of the National Health Laboratory Service, Johannesburg, South Africa.
⁶ MRC/Wits Rural Public Health and Health Transitions Research Unit (Agincourt), School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
⁷ INDEPTH Network, Accra, Ghana.
⁸ Epidemiology and Global Health Unit, Department of Public Health and Clinical Medicine, Umeâ University, Umeâ, Sweden.
⁹ Department of Disease Control, London School of Hygiene & Tropical Medicine, London, UK.
¹⁰ Africa Health Research Institute, Somkhele, South Africa.
¹¹ School of Nursing and Public Health, University of KwaZulu-Natal, Durban, South Africa.

Abstract

Introduction: Verbal autopsy (VA) can be integrated into civil registration and vital statistics systems, but its accuracy in determining HIV-associated causes of death (CoD) is uncertain. We assessed the sensitivity and specificity of VA questions in determining HIV status and antiretroviral therapy (ART) initiation and compared HIV-associated mortality fractions assigned by different VA interpretation methods.

Methods: Using the WHO 2012 instrument with added ART questions, VA was conducted for deaths among adults with known HIV status (356 HIV positive and 103 HIV negative) in South Africa. CoD were assigned using physician-certified VA (PCVA) and computer-coded VA (CCVA) methods and compared with documented HIV status.

Results: The sensitivity of VA questions in detecting HIV status and ART initiation was 84.3% (95% CI 80 to 88) and 91.0% (95% CI 86 to 95); 283/356 (79.5%) HIV-positive individuals were assigned HIV-associated CoD by PCVA, 166 (46.6%) by InterVA-4.03, 201 (56.5%) by InterVA-5, and 80 (22.5%) and 289 (81.2%) by SmartVA-Analyze V.1.1.1 and V.1.2.1. Agreement between PCVA and older CCVA methods was poor (chance-corrected concordance [CCC] <0; cause-specific mortality fraction [CSMF] accuracy ≤56%) but better between PCVA and updated methods (CCC 0.21-0.75; CSMF accuracy 65%-98%). All methods were specific (specificity 87% to 96%) in assigning HIV-associated CoD.

Conclusion: All CCVA interpretation methods underestimated the HIV-associated mortality fraction compared with PCVA; InterVA-5 and SmartVA-Analyze V.1.2.1 performed better than earlier versions. Changes to VA methods and classification systems are needed to track progress towards targets for reducing HIV-associated mortality.

Keywords: AIDS; HIV; epidemiology; health systems; medical demography.

Abstract

Grants and funding