AIDS and Behavior

, Volume 17, Issue 2, pp 649–661 | Cite as

Differences Between Seven Measures of Self-Reported Numbers of Clients of Female Sex Workers in Southern India: Implications for Individual- and Population-Level Analysis

  • Kathleen N. Deering
  • P. Vickerman
  • M. Pickles
  • S. Moses
  • J. F. Blanchard
  • B. M. Ramesh
  • S. Isac
  • M.-C. Boily
Original Paper


Quantifying sexual activity of sub-populations with high-risk sexual behaviour is important in understanding HIV epidemiology. This study examined inconsistency of seven outcomes measuring self-reported clients per month (CPM) of female sex workers (FSWs) in southern India and implications for individual/population-level analysis. Multivariate negative binomial regression was used to compare key social/environmental factors associated with each outcome. A transmission dynamics model was used to assess the impact of differences between outcomes on population-level FSW/client HIV prevalence. Outcomes based on ‘clients per last working day’ produced lower estimates than those based on ‘clients per typical day’. Although the outcomes were strongly correlated, their averages differed by approximately two-fold (range 39.0–79.1 CPM). The CPM measure chosen did not greatly influence standard epidemiological ‘risk factor’ analysis. Differences across outcomes influenced HIV prevalence predictions. Due to this uncertainty, we recommend basing population-based estimates on the range of outcomes, particularly when assessing the impact of interventions.


Measurement Methodological issues Mathematical modelling Sexual behaviour Sexual partners Female sex workers India 



KND is supported by a post-doctoral research fellowship from the Canadian Institutes of Health Research and the Michael Smith Foundation for Health Research. Support for this study was provided by the Bill and Melinda Gates Foundation. The views expressed herein are those of the authors and do not necessarily reflect the official policy or position of the Bill and Melinda Gates Foundation.

Supplementary material

10461_2012_279_MOESM1_ESM.doc (74 kb)
Supplementary material 1 (DOC 74 kb)
10461_2012_279_MOESM2_ESM.doc (130 kb)
Supplementary material 2 (DOC 131 kb)


  1. 1.
    Gillmore MR, Leigh BC, Hoppe MJ, Morrison DM. Comparison of daily and retrospective reports of vaginal sex in heterosexual men and women. J Sex Res. 2009;46:1–6.CrossRefGoogle Scholar
  2. 2.
    Fenton KA, Johnson AM, McManus S, Erens B. Measuring sexual behaviour: methodological challenges in survey research. Sex Transm Infect. 2001;77:84–92.PubMedCrossRefGoogle Scholar
  3. 3.
    Catania JA, Gibson DR, Marin B, Coates TJ, Greenblatt RM. Response bias in assessing sexual behaviors relevant to HIV transmission. Eval Program Plann. 1990;13(1):19–29.CrossRefGoogle Scholar
  4. 4.
    Morrison-Beedy D, Carey MP, Tu X. Accuracy of audio computer-assisted self-interviewing (ACASI) and self-administered questionnaires for the assessment of sexual behavior. AIDS Behav. 2006;10(5):1090–7165.CrossRefGoogle Scholar
  5. 5.
    Ole-King’Ori N, Klepp KI, Kissila PE, Biswalo PM, Mnyika KS. Demographic and AIDS-related characteristics of consenters to a population-based HIV-survey: results from a pilot study in Arusha. Tanzania. East Afr Med J. 1994;71(8):483–9.PubMedGoogle Scholar
  6. 6.
    Johnson AM, Mercer CH, Erens B, Copas AJ, McManus S, Wellings K, et al. Sexual behaviour in Britain: partnerships, practices, and HIV risk behaviours. Lancet. 2001;358(9296):1835–42.PubMedCrossRefGoogle Scholar
  7. 7.
    Buvé A, Lagarde E, Caraël M, Rutenberg N, Ferry B, Glynn JR, et al. Interpreting sexual behaviour data: validity issues in the multicentre study on factors determining the differential spread of HIV in four African cities. AIDS. 2001;15(Suppl 4):S117–26.PubMedCrossRefGoogle Scholar
  8. 8.
    Edgardh K. Sexual behaviour and early coitarche in a national sample of 17 year old Swedish girls. Sex Transm Infect. 2000;76:98–102.PubMedCrossRefGoogle Scholar
  9. 9.
    MıC Zea, Reisen CA, Díaz RM. Methodological issues in research on sexual behavior with latino gay and bisexual men. Am J Commun Psychol. 2003;31(3/4):281–91.CrossRefGoogle Scholar
  10. 10.
    Schrimshaw EW, Rosario M, Meyer-Bahlburg HFL, Scharf-Matlick AA. Test-retest reliability of self-reported sexual behavior, sexual orientation, and psychosexual milestones among gay, lesbian, and bisexual youths. Arch Sex Behav. 2006;35(2):225–34.PubMedCrossRefGoogle Scholar
  11. 11.
    Upchurch DM, Lillard LA, Aneshensel CS, Li NF. Inconsistencies in reporting the occurrence and timing of first intercourse among adolescents. J Sex Res. 2002;39(3):197–206.PubMedCrossRefGoogle Scholar
  12. 12.
    Deuchert E, Brody S. Plausible and implausible parameters for mathematical modeling of nominal heterosexual HIV transmission. Ann Epidemiol. 2007;17(3):237–44.PubMedCrossRefGoogle Scholar
  13. 13.
    Brewer DD, Potterat JJ, Garrett SB, Muth SQ, Roberts JMJ, Kasprzyk D, et al. Prostitution and the sex discrepancy in reported number of sexual partners. Proc Natl Acad Sci USA. 2000;97:12385–8.PubMedCrossRefGoogle Scholar
  14. 14.
    Wiederman MW. The truth must be in here somewhere: examining the gender discrepancy in self-reported lifetime number of sex partners. J Sex Res. 1997;34(4):375–86.CrossRefGoogle Scholar
  15. 15.
    Roberts JM, Brewer DD. Measures and tests of heaping in discrete quantitative distributions. J Appl Stat. 2001;28(7):887–96.CrossRefGoogle Scholar
  16. 16.
    Schroder KEE, Carey MP, Vanable PA. Methodological challenges in research on sexual risk behavior: I. Item content, scaling, and data analytical options. Ann Behav Med. 2003;26(2):76–103.PubMedCrossRefGoogle Scholar
  17. 17.
    Brisson M, Boily M-C, Masse BR, Adrien A, Leaune V. Highlights of the sexual activity of the heterosexual population in the province of Quebec. Sex Transm Infect. 1999;75:296–9.PubMedCrossRefGoogle Scholar
  18. 18.
    Ramesh BM, Moses S, Washington R, Isac S, Mohapatra B, Mahagaonkar SB, et al. Determinants of HIV prevalence among female sex workers in four south Indian states: analysis of cross-sectional surveys in twenty-three districts. AIDS. 2008;22(Suppl 5):S35–44.PubMedCrossRefGoogle Scholar
  19. 19.
    Sarkar S. Community engagement in HIV prevention in Asia: going from ‘for the community’ to ‘by the community’ must we wait for more evidence? Sex Transm Infect. 2010;86(Suppl 1):i2–3.PubMedCrossRefGoogle Scholar
  20. 20.
    Bradley J, Moses S, Blanchard JF, Rajaram S, Ramesh BM, Verma S, et al. Assessing reported condom use among female sex workers in southern India through examination of condom availability. Sex Transm Infect. 2010;86(Suppl 1):i44–8.PubMedCrossRefGoogle Scholar
  21. 21.
    Cwikel J, Ilan K, Chudakov B. Women brothel workers and occupational health risks. J Epidemiol Community H. 2003;57:809–15.CrossRefGoogle Scholar
  22. 22.
    Deering KN, Tyndall MW, Shoveller J, Moses S, Blanchard JF, Shaw SY, et al. Factors associated with numbers of client partners of female sex workers across five districts in South India. Sex Transm Dis. 2010;37:687–95.PubMedCrossRefGoogle Scholar
  23. 23.
    Fung IC-H, Guinness L, Vickerman P, Watts C, Vannela G, Vadhvana J, et al. Modelling the impact and cost-effectiveness of the HIV intervention programme amongst commercial sex workers in Ahmedabad, Gujarat, India. BMC Public Health. 2007;7:195.PubMedCrossRefGoogle Scholar
  24. 24.
    Aral SO. Determinants of STD epidemics: implications for phase appropriate intervention strategies. Sex Transm Infect. 2002;78:i3–13.PubMedCrossRefGoogle Scholar
  25. 25.
    Watts C, Zimmerman C, Foss AM, Hossain M, Cox A, Vickerman P. Remodelling core group theory: the role of sustaining populations in HIV transmission. Sex Transm Infect. 2010;86:iii85–92.PubMedCrossRefGoogle Scholar
  26. 26.
    Hanck SE, Blankenship KM, Irwin KS, West BS, Kershaw T. Assessment of self-reported sexual behavior and condom use among female sex workers in India using a polling box approach: a preliminary report. Sex Transm Dis. 2008;35(5):489–94.PubMedCrossRefGoogle Scholar
  27. 27.
    Pool R, Montgomery CM, Morar NS, Mweemba O, Ssali A, Gafos M, et al. Assessing the accuracy of adherence and sexual behaviour data in the MDP301 vaginal microbicides trial using a mixed methods and triangulation model. PLoS ONE. 2010;5(7):e11632.PubMedCrossRefGoogle Scholar
  28. 28.
    Blanchard JF, Halli S, Ramesh BM, Bhattacharjee P, Washington RG, O’Neil J, et al. Variability in the sexual structure in a rural Indian setting: implications for HIV prevention strategies. Sex Transm Infect. 2007;83(Suppl 1):i30–6.PubMedCrossRefGoogle Scholar
  29. 29.
    Avahan, The India AIDS initiative: the business of HIV prevention at Scale 2008. Available from:
  30. 30.
    Blanchard JF, Khan A, Bokhari A. Variations in the population size, distribution and client volume among female sex workers in seven cities of Pakistan. Sex Transm Infect. 2008;84:ii24–7.PubMedCrossRefGoogle Scholar
  31. 31.
    Pickles M, Foss AM, Vickerman P, Deering KN, Verma S, Demers E, et al. Interim modelling analysis to validate reported increases in condom use and assess HIV infections averted among female sex workers and clients in southern India following a targeted HIV prevention programme. Sex Transm Infect. 2010;86:i33–43.PubMedCrossRefGoogle Scholar
  32. 32.
    Boily MC, Lowndes CM, Vickerman P, Kumaranayake L, Blanchard J, Moses S, et al. Evaluating large-scale HIV prevention interventions: study design for an integrated mathematical modelling approach. Sex Transm Infect. 2007;83:582–9.PubMedCrossRefGoogle Scholar
  33. 33.
    Anderson RM, May RM. Infectious diseases of humans: dynamics and control. Oxford: Oxford University Press; 1991.Google Scholar
  34. 34.
    Garnett GP, White PJ, Ward H. Fewer partners or more condoms? Modelling the effectiveness of STI prevention interventions. Sex Transm Infect. 2008;84:ii4–11.PubMedCrossRefGoogle Scholar
  35. 35.
    StataCorp. Stata Statistical Software: Release 9. 9.2 ed. College Station: StataCorp LP; 2005.Google Scholar
  36. 36.
    Rosner B. Fundamentals of biostatistics. 6th ed. Pacific Grove: Duxbury Press; 2005.Google Scholar
  37. 37.
    Hilbe J. Negative binomial regression. New York: Cambridge University Press; 2007.CrossRefGoogle Scholar
  38. 38.
    Deering K. The structure of sex work: variability in the numbers and types of sex partners of female sex workers in southern India [Dissertation]. Vancouver: University of British Columbia; 2011.Google Scholar
  39. 39.
    McAuliffe TL, DiFranceisco W, Reed BR. Effects of question format and collection mode on the accuracy of retrospective surveys of health risk behavior: a comparison with daily sexual activity diaries. Health Psychol. 2007;26:60–7.PubMedCrossRefGoogle Scholar
  40. 40.
    Schroder KEE, Carey MP, Vanable PA. Methodological challenges in research on sexual risk behavior: II. Accuracy of self-reports. Ann Behav Med. 2003;26:104–23.PubMedCrossRefGoogle Scholar
  41. 41.
    Verbrugge LM. Health diaries. Med Care. 1980;18:73–95.PubMedCrossRefGoogle Scholar
  42. 42.
    Armstrong BK, White E, Saracci R. Principles of exposure measurement in epidemiology. New York: Oxford University Press; 1992.Google Scholar
  43. 43.
    Hamilton DT, Handcock MS, Morris M. Degree distributions in sexual networks: a framework for evaluating evidence. Sex Transm Dis. 2008;35(1):30–40.PubMedCrossRefGoogle Scholar
  44. 44.
    Bailey SL, Gao W, Clark DB. Diary study of substance use and unsafe sex among adolescents with substance use disorders. J Adolesc Health. 2006;38(297):e13–20.PubMedGoogle Scholar
  45. 45.
    Shrier LA, Shih MC, Hacker L, deMoor C. A momentary sampling study of the affective experience following coital events in adolescents. J Adolesc Health. 2007;40(357):e1–8.PubMedGoogle Scholar
  46. 46.
    Lim MSC, Hocking JS, Hellard ME, Aitken CK. SMS STI: a review of the uses of mobile phone text messaging in sexual health. Int J STD AIDS. 2008;19(5):287–90.PubMedCrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC 2012

Authors and Affiliations

  • Kathleen N. Deering
    • 1
  • P. Vickerman
    • 2
  • M. Pickles
    • 3
  • S. Moses
    • 4
    • 5
    • 6
  • J. F. Blanchard
    • 5
    • 6
  • B. M. Ramesh
    • 7
  • S. Isac
    • 7
  • M.-C. Boily
    • 3
  1. 1.Division of AIDS, Department of Medicine, Faculty of MedicineUniversity of British ColumbiaVancouverCanada
  2. 2.London School of Hygiene and Tropical MedicineLondonUK
  3. 3.Department of Infectious Disease EpidemiologyImperial CollegeLondonUK
  4. 4.Department of Medical MicrobiologyUniversity of ManitobaWinnipegCanada
  5. 5.Department of Community Health SciencesUniversity of ManitobaWinnipegCanada
  6. 6.Centre for Global Public HealthUniversity of ManitobaWinnipegCanada
  7. 7.Karnataka Health Promotion TrustBangaloreIndia

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