AIDS and Behavior

, Volume 21, Issue 8, pp 2394–2400 | Cite as

Estimating the Population Size of Female Sex Worker Population in Tehran, Iran: Application of Direct Capture–Recapture Method

  • Manoochehr Karami
  • Salman Khazaei
  • Jalal Poorolajal
  • Alireza Soltanian
  • Mansour SajadipoorEmail author
Original Paper


There is no reliable estimate of the size of female sex workers (FSWs). This study aimed to estimate the size of FSWs in south of Tehran, Iran in 2016 using direct capture–recapture method. In the capture phase, the hangouts of FSWs were mapped as their meeting places. FSWs who agreed to participate in the study tagged with a T-shirt. The recapture phase was implemented at the same places tagging FSWs with a blue bracelet. The total estimated size of FSWs was 690 (95% CI 633, 747). About 89.43% of FSWs experienced sexual intercourse prior to age 20. The prevalence of human immunodeficiency virus infection among FSWs was 4.60%. The estimated population size of FSWs was much more than our expectation. This issue must be the focus of special attention for planning prevention strategies. However, alternative estimates require to estimating the number FSWs, reliably.


Sex workers Human immunodeficiency virus Women Capture–recapture Iran 



This study has been adapted from an MSc thesis at Hamadan University of Medical Sciences. The Authors would like to thank all contributors and participants who make this study project possible.


The study was partially funded by the Vice-chancellor for research and Technology, Hamadan University of Medical Sciences (Grant No. 9403121140).

Compliance with Ethical Standards

Conflict of interest

The authors have no conflict of interest to declare for this study.

Ethical Approval

This study was approved by the Ethics Committee of Hamadan University of Medical Sciences (UMSHA.REC.1394.56).

Informed Consent

Informed consent was obtained from all individual participants included in the study.


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Copyright information

© Springer Science+Business Media New York 2017

Authors and Affiliations

  • Manoochehr Karami
    • 1
    • 2
  • Salman Khazaei
    • 3
  • Jalal Poorolajal
    • 4
  • Alireza Soltanian
    • 5
  • Mansour Sajadipoor
    • 2
    Email author
  1. 1.Social Determinants of Health Research CenterHamadan University of Medical SciencesHamadanIran
  2. 2.Department of Epidemiology, School of Public HealthHamadan University of Medical SciencesHamadanIran
  3. 3.Department of Biostatistics and Epidemiology, School of Public HealthTehran University of Medical SciencesTehranIran
  4. 4.Research Center for Health SciencesHamadan University of Medical SciencesHamadanIran
  5. 5.Modeling of Noncommunicable Diseases Research CenterHamadan University of Medical SciencesHamadanIran

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