Demographic and behavioural factors associated with chlamydia incident and re-infection among a cohort of sexually active 16 to 25 year old women.

* Analysis of incident infections includes re-infection.a = confidence interval;b = adjusted for age, employment, clinic type, number of new partners and recent antibiotic use;c = adjusted for clinic type;d = previous positive chlamydia test reported on questionnaire or diagnosed at time of recruitment into the study.