Table 2

Absolute numbers of chlamydia tests, testing rates and estimated testing rate ratio obtained from the mixed-effects Poisson regression model during and 9 months following the intervention period by study group

CIRT intervention practicesCIRT control practicesCIRT non-randomised practices
Number of practices7681286
Number of patients66 95479 360287 964
Study periodDuring9 m postDuring9 m postDuring9 m post
Chlamydia screening tests through NCSP
 Number in patients 15–24 years2 9071 7392379167976145.653
 Rate of tests/100 patients 15–24 years4.343.463.002.822.662.63
 Estimated testing rate ratio mixed effects Poisson regression (CI) from intention to treat1.76 (1.24 to 2.48)1.57 (1.07 to 2.30)ReferenceReference0.93 (0.71 to 1.23)0.94 (0.69–1.27)
Positive tests (chlamydia infections diagnosed) through NCSP screening tests
 Number in patients 15–24 years164108182118548382
 Rate/1000 patients 15–24 years2.
 Estimated infections (CI) detected rate ratio mixed-effects Poisson regression from per-protocol analysis1.3 (0.9–1.9)
1.4 (1.0–1.9)
1.4 (0.9–2.3)
1.6 (1.1–2.3)
ReferenceReferenceNot in per protocol analysisNot in per protocol analysis
  • CIRT, Chlamydia Intervention Randomised controlled Trial; NCSP, National Chlamydia Screening Programme.