The National Chlamydia Screening Programme currently being rolled out in health and non-health settings in England uses an opportunistic approach, where young men and women under the age of 25 are offered screening at the time of attendance.

Some large-scale studies have also looked at a register-based approach, where subjects receive and submit the test by post. A study has suggested that this may improve screening coverage in young men.

This study was based in Scotland and compared chlamydia positives and risk factors in different settings. Testing kits were distributed in settings such as pharmacies, young people's drop-ins and record stores; on-site testing was offered in further education colleges and a university as well as a young person's sexual health clinic. Almost 4,500 samples were provided (3,793 women, 682 men).

Overall, positives for chlamydia were found in 12.3% (95% CI, 10.1 to 15.0) of young men and 10.6% (9.7 to 11.6) of young women. Postal testing was the main source of testing for young men, accounting for 80% of all tests; in women there was no difference in the use of postal and clinic settings (46% and 48% respectively).

Although the number of samples from men is increasing year on year in the English National Chlamydia Screening Programme, it is still a fraction of that from young women. This study supports the use of register-based postal testing, which might increase the coverage of chlamydia screening and seems to be a method favoured by young men.

There is no doubt that GP-based registers would be used for postal screening on a larger scale. If that is the case, primary care may be involved in a 'call and recall' system of screening, just like the cervical cytology programme.

Williamson LM, Scott G, Carrick-Anderson K et al. Chlamydia trachomatis testing among 13-25-year-olds in non-genitourinary medicine settings. J Fam Plann Reprod Health Care 2007;33:177-82