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Evaluating large-scale HIV prevention interventions: study design for an integrated mathematical modelling approach
  1. M-C Boily1,
  2. C M Lowndes4,
  3. P Vickerman5,
  4. L Kumaranayake5,
  5. J Blanchard3,
  6. S Moses3,
  7. B M Ramesh6,
  8. M Pickles1,
  9. C Watts5,
  10. R Washington7,
  11. S Reza-Paul3,
  12. A C Labbe8,
  13. R M Anderson1,
  14. K N Deering3,
  15. M Alary2,
  16. on behalf of the CHARME-India team
  1. 1Department of Infectious Diseases Epidemiology, Imperial College, London, UK
  2. 2Centre Hopitalier affilié Universitaire de Québec (CHA), Québec, Canada
  3. 3University of Manitoba, Manitoba, Canada
  4. 4Health Protection Agency, London, UK
  5. 5London School of Hygiene & Tropical Medicine (LSHTM), London, UK
  6. 6Karnataka Health Promotion Trust (KHPT), Bangalore, India
  7. 7St. John’s Medical College, Bangalore, India
  8. 8University of Montreal, Montreal, Canada
  1. Correspondence to:
 Dr Marie-Claude Boily
 Department of Infectious Disease Epidemiology, Faculty of Medicine, Imperial College, Norfolk Place, W2 1PG, London, UK; mc.boily{at}


Background: There is an urgent need to evaluate HIV prevention interventions, thereby improving our understanding of what works, under what circumstances and what is cost effective.

Objectives: To describe an integrated mathematical evaluation framework designed to assess the population-level impact of large-scale HIV interventions and applied in the context of Avahan, the Indian AIDS Initiative, in southern India. The Avahan Initiative is a large-scale HIV prevention intervention, funded by the Bill & Melinda Gates Foundation, which targets high-risk groups in selected districts of the six states most affected by the HIV/AIDS epidemic (Maharashtra, Karnataka, Tamil Nadu, Andhra Pradesh, Nagaland and Manipur) and along the national highways.

Methods: One important component of the monitoring and evaluation of Avahan relies on an integrated mathematical framework that combines empirical biological and behavioural data from different subpopulations in the intervention areas, with the use of tailor-made transmission dynamics models embedded within a Bayesian framework.

Results: An overview of the Avahan Initiative and the objectives of the monitoring and evaluation of the intervention is given. The rationale for choosing this evaluation design compared with other possible designs is presented, and the different components of the evaluation framework are described and its advantages and challenges are discussed, with illustrated examples.

Conclusions: This is the first time such an approach has been applied on such a large scale. Lessons learnt from the CHARME project could help in the design of future evaluations of large-scale interventions in other settings, whereas the results of the evaluation will be of programmatic and public health relevance.

  • C-RCT, community randomised controlled trial
  • CrI, credibility interval
  • FSW, female sex worker
  • GPS, general population survey
  • IBBA, integrated behavioural and biological assessment
  • M&E, monitoring and evaluation
  • MFSW, male and female commercial sex worker
  • MIS, management information system
  • MSM, men who have sex with men
  • SBS, special behavioural survey
  • STI, sexually transmitted infection

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  • Funding: Support for this research was provided by the Bill & Melinda Gates Foundation through Avahan, its India AIDS Initiative.

  • Competing interests: None.

  • Contributions: MCB, CML, PV, LK, JB, SM, BMR, CW, RW, ACL, RMA, SRP and MA contributed to the different aspects of the study design. KD and MP designed the mathematical models used to produce simulation results and figures. MP helped with the design of the Bayesian framework. MCB wrote the first draft of the manuscript with the help of CML. KD, MP, MA, PV, LK, JB, SM, and MA contributed to the different drafts of the manuscript.

    The views expressed herein are those of the authors and do not necessarily reflect the official policy or position of the Bill & Melinda Gates Foundation and Avahan.

    CHARME-India is the CHA—HIV/AIDS Research, Monitoring and Evaluation Project, India. The CHARME-India team includes the investigators RMA, MA, JB, MCB, LK, ACL, CML, SM, BMR, SRP, PV, CW, RW and co-workers S Chandrashekar, KN Deering, A Foss, K Gurav, AA Jayachandran, S Joseph, B Mahapatra, A Phillips and M Pickles. The main collaborating institutions include CHA, University of Manitoba, KHPT, St John’s Medical College, Imperial College, LSHTM; collaborating institutions for field work include the Tata Institute of Social Sciences, Mumbai, and the Centre for Media Studies, Hyderabad.

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