A study, in Sexually Transmitted Infections, has found that although GPs are testing for and diagnosing more chlamydia infections, they are disproportionately targeting women over the age of 24 and men are still underrepresented.

The investigations used population data from the General Practice Research Database (GPRD), which contains anonymised data on 4.7% of the UK population. It is broadly demographically representative of the UK population but there is slight underrepresentation of Inner London and Scotland, because GPRD relies on practices using VISION software to contribute to the database, so practices using other software, such as EMIS, are excluded.

The study investigated the rates of chlamydia testing, diagnostic episodes, treatments and referrals between 1990 and 2004 in patients aged 12-64.

The study found that rates of chlamydia testing increased more in women than in men; from 100 per 100,000 patient-years and 10 per 100,000 patient-years in women and men respectively before 1998, to 1,439 per 100,000 patient-years and 74 per 100,000 patient-years respectively in 2004.

Testing rates were highest among women aged 20-24, followed by women aged 25-34. A quarter of all diagnoses of chlamydia infection in women and 5% in men were made and treated by GPs in 2004.

GPs generally perform an STI test only at the request of patients - usually women in their mid-twenties.

If we really want to encourage GPs to test and treat those at risk, I would suggest rewarding GPs for case finding and treating STIs, expanding chlamydia screening to general practice and encouraging men and women under 25 to attend their GPs for chlamydia screening.

Hughes G, Williams T, Simms I et al. Use of a primary care database to determine trends in genital chlamydia testing, diagnostic episodes and management in UK general practice, 1990-2004. Sex Transm Infect 2007;83:310-13