Conventional mode of contact tracing where the partners were asked by either the index patient or demanded by the counsellor to attend a clinic for C. trachomatis testing. The date of testing for chlamydia of the study subject i e a sexual partner to a chlamydia infected index patient was noted. Those partners being C trachomatis positive were referred to the STD-clinic for contact tracing and following the same study arm a the index patient.

The intervention: Self-sampling of sexual partners to infected index patient for chlamydia by urine test or vaginal sampling at home. They sent the kit tube to a microbiological laboratorium for analysis. The test kit was sent by post by the counsellor at the STD-clinic or distributed via the index patient. The partner in this arm was informed about the test result from the STD-clinic and those tested C trachomatis positive were given an appointment for treating and contact tracing as soon as possible. Their partners were not randomised but following the same mode. The days from the counselling conversation with the index patient to the date of testing was measured and compared with partners tested following arm 1 mode.

Difference in time, measured as days from the meeting between the index patient and the counsellor (i.e. the eliciting of sexually partners) until the date of C. trachomatis testing of partners, if sexual partners had attended a clinic for testing or had the opportunity of home-sampling.