To investigate the effect of time since last urination on chlamydial positivity rates in men, the authors conducted a prospective study on 1,649 men attending a genitourinary clinic. Participants were asked for the last time of urination before obtaining their urine samples for chlamydia testing with the Cobas Amplicor polymerase chain reaction (PCR) assay.

Researchers found that 621 (37.6 percent (95 percent confidence interval [CI] 35.3 percent to 39.9 percent)) of the men had a voiding interval of less than two hours. No statistical evidence indicated a difference in the positivity rate of chlamydia infection among men with a voiding interval of less than two hours (106/621, 17.1 percent) and that of men with a voiding interval of two hours or longer (170/1,028, 16.5 percent); difference in proportions 0.5 percent (95 percent CI to 3.2 percent to 4.3 percent), p=0.779.

"Voiding interval does not have a significant impact on the performance of the Cobas Amplicor PCR assay in men," the authors concluded.

www.aegis.org