Background: CHLAMYDIA TRACHOMATIS: is the most prevalent sexually transmitted bacterial disease in Norway. The purpose of the present study was to describe testing patterns and prevalence of Chlamydia in a Norwegian county, with special focus on urine-based testing. :
Material and methods: Data on all Chlamydia tests 1990 - 2006 for men and women 15 - 59 years old, living in Sør-Trøndelag County, were retrieved from a laboratory database. 243 671 Chlamydia test results were eligible for analysis.
Results: Testing rates were considerably higher for men than for women in all age-groups throughout the study period. Urine-based testing was introduced for men in 2001 and for women in 2004. In 2006, urine-based testing comprised most of the test volume for men (15 - 19 year-olds: 87.9 %, 20 - 24 year-olds: 81.7 %), but far less for women (15 - 19 year-olds: 55.8 %, 20 - 24 year-olds: 26.5 %). The proportion of positive tests was higher for women with a urine-based test than for those with a sample from the cervix (2006: 15 - 19 year-olds: 18.0 % versus 13.5 %, 20 - 24 year-olds: 16.9 % versus 9.6 %).
Interpretation: Male testing rates have increased after urine-based testing for Chlamydia became an option. Young women delivering urine samples are more often positive than women with cervix samples.