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Theoretical and Empirical Comparisons of Methods to Estimate the Size of Hard-to-Reach Populations: A Systematic Review

AIDS and Behavior volume 21, pages 2188–2206 (2017)Cite this article

Abstract

Worldwide, the HIV epidemic is concentrated among hidden populations (i.e., female sex workers, men who have sex with men, and people who inject drugs). To understand the true scope and scale of the HIV epidemic, estimates of the sizes of these populations are needed. Various methods are available to enumerate hidden populations, but the degree of agreement between these methods has not been formally evaluated. We systematically reviewed the peer-reviewed literature to assess the extent to which different population size estimation methods provide the same estimate of a target population. Of the 341 studies identified from our search, 25 met our eligibility criteria. Twenty-one unique methods were documented. The service multiplier method was the most common in the review. Eighty target populations were estimated, covering 16 countries. We observed variable population size estimates, with little agreement between methods. We note trends in the relative performance of individual methods.

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Acknowledgements

This research was supported by Grant T32 MH19105 from the National Institutes of Mental Health of the U.S. Public Health Service

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Affiliations

  1. Center for AIDS Prevention Studies, TAPS Fellowship Program, University of California, San Francisco, Mission Hall, 550 16th Street, 3rd Floor, Mail Code 0886, San Francisco, CA, 94158, USA

    Paul Wesson

  2. Department of Epidemiology, School of Public Health, University of California, Berkeley, Berkeley, CA, USA

    Paul Wesson & Arthur Reingold

  3. Department of Epidemiology, University of California, San Francisco, San Francisco, CA, USA

    Willi McFarland

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  1. Paul Wesson
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  2. Arthur Reingold
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  3. Willi McFarland
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Correspondence to Paul Wesson.

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Wesson, P., Reingold, A. & McFarland, W. Theoretical and Empirical Comparisons of Methods to Estimate the Size of Hard-to-Reach Populations: A Systematic Review. AIDS Behav 21, 2188–2206 (2017). https://doi.org/10.1007/s10461-017-1678-9

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Keywords

  • Population size estimation
  • Hidden populations
  • HIV/AIDS
  • Men who have sex with men
  • People who inject drugs