The quality of evidence is downgraded by inconsistency (unexplained variability in results) and by imprecise results (wide confidence intervals).
A Cochrane review [Abstract] 1 included 6 studies with a total of 359 078 subjects. A cluster-controlled trial in women and men in the general population in the Netherlands found no change in chlamydia test positivity after 3 yearly invitations (intervention 4.1% vs control 4.3%, RR 0.96, 95% CI 0.84 to 1.09; 1 trial, n=317 at first screening invitation; very low quality evidence, because uptake of the intervention was low, maximum 16%). A cluster-randomised high quality trial in female sex workers in Peru found a reduction in chlamydia prevalence after 4 years (adjusted RR 0.72, 95% CI 0.54 to 0.98; 1 trial, n=4465).Four RCTs examined the effect of chlamydia screening on pelvic inflammatory disease (PID) in women 12 months after a single screening offer. The risk of PID was lower in women in intervention than control groups (RR 0.68, 95% CI 0.49 to 0.94, I²=7%; 4 trials, n=21 686). However, the estimated effect of chlamydia screening in 2 RCTs at low risk of bias (RR 0.80, 95% CI 0.55 to 1.17) was compatible with no effect.The risk of epididymitis in men invited for screening, 12 months after a single screening offer, showed a trend of lower risk than in those not invited; the confidence interval was wide and compatible with no effect (RR 0.80, 95% CI 0.45 to 1.42; 1 high quality trial, n=14 980).
Date of latest search: 9 June 2016
Primary/Secondary Keywords