Background The National Chlamydia Screening Programme (NCSP), established nationally in England in 2008, aims to prevent and control chlamydia infection in young adults under 25 years of age through opportunistic community based testing.

Aim We wished to validate the NCSP estimates of chlamydia screening coverage in the target population of young adults by comparing to self-reported chlamydia testing among participants to the Health Survey for England (HSE).

Methods Chlamydia screening coverage is calculated centrally by combining the number of tests reported from three sources of data: NCSP; sexual health clinics; and laboratories. All three sources provide data by age and sex. HSE is an annual general health survey of a nationally representative selection of households in England. In 2010, questions on previous history of testing for chlamydia were asked of all 4259 individuals aged 16–54 who were interviewed. Analyses presented here are limited to the 725 young adults aged 16–24 years old.

Results In 2010, NCSP estimated that 2.2 million chlamydia tests were performed in England among young adults aged 15–24 years old, representing up to 33% of the target population (43% of females and 24% of males). In HSE 2010, 44% of females (177/402) and 27% of males (87/323) reported having ever had a chlamydia test. The proportion who reported having had chlamydia test in the last year was lower for both females (27%; 109/402) and males (17%; 55/323).

Conclusion We have demonstrated the progress made by NCSP in achieving high national levels of coverage. Estimated coverage rates in 2010 reported by NCSP were slightly higher than those recorded by HSE which may be in part due to the inclusion of those who have had repeat chlamydia tests. The data collected by HSE has proved a valuable source of data with which to monitor the progress of NCSP in achieving national targets for testing coverage and improve the delivery of the programme.