Article Text

other Versions

Predicting the population impact of chlamydia screening programmes: comparative mathematical modelling study
  1. Mirjam Kretzschmar (mirjam.kretzschmar{at}
  1. University Medical Centre, Utrecht, Netherlands
    1. Katherine ME Turner (katy.turner{at}
    1. University of Bristol, United Kingdom
      1. Pelham M Barton (p.m.barton{at}
      1. University of Birmingham, United Kingdom
        1. W John Edmunds (john.edmunds{at}
        1. London School of Hygiene and Tropical Medicine, United Kingdom
          1. Nicola Low (low{at}
          1. University of Bern, Switzerland


            Background: Published individual-based, dynamic sexual network modelling studies reach different conclusions about the population impact of screening for Chlamydia trachomatis. Our objective was to conduct a direct comparison of the effect of organised chlamydia screening in different models.

            Methods: We used three models simulating population level sexual behaviour, chlamydia transmission, screening and partner notification. Parameters describing a hypothetical annual opportunistic screening program in 16–24 year olds were standardised, while other parameters from the three original studies were retained. Model predictions of the change in chlamydia prevalence were compared under a range of scenarios.

            Results: Initial overall chlamydia prevalence rates were similar in women but not men and there were age- and sex-specific differences between models. The number of screening tests carried out was comparable in all models but there were large differences in the predicted impact of screening. After 10 years of screening, the predicted reduction in chlamydia prevalence in women aged 16–44 years ranged from 4% to 85%. Screening men and women had a greater impact than screening women alone in all models. There were marked differences between models in assumptions about treatment seeking and sexual behaviour before the start of the screening intervention.

            Conclusions: Future models of chlamydia transmission should be fitted to both incidence and prevalence data. This meta-modelling study provides essential information for explaining differences between published studies and increasing the utility of individual-based chlamydia transmission models for policy making.

            Statistics from

            Request permissions

            If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.