Archived Comments for:
Community-based trial of screening for Chlamydia trachomatis to prevent pelvic inflammatory disease: the POPI (prevention of pelvic infection) trial
Re: Community-based trail of screening for Chlamydia trachomatis to prevent pelvic inflammatory disease: the POPI (prevention of pelvic infection) trial
T Aldeen, Dr T Aldeen, Devon PCT
19 December 2008
Dear Sir,
I read your study with great interest as we still lack information about the natural history of Chlamydia and PID.
However, your diagnosis of PID relies mainly on the clinical history and I would like to remind you that PID may be symptomatic or asymptomatic and wonder how could you identify asymptomatic PID in your participants. Even symptomatic PID, clinical symptoms and signs lack sensitivity and specificity (the positive predictive value of a clinical diagnosis is 65-90% compared to laparoscopic diagnosis). Also the absence of genital Chlamydia infection does not exclude PID (http://www.bashh.org/documents/118/118.pdf).
Further, although the study information sheet explains the risk, it is challenging to leave women in the control arm with possible asymptomatic genital infection untreated for one year. Similarly, treating women who become symptomatic and infected with Chlamydia in the control arm may eliminate the efforts of reaching the natural history of Chlamydia. Equally, participants may choose to use the barrier method after reading the study information sheet and this may reduce the prevalence of Chlamydia in the study sample, especially the study is targeting university students and excluding uneducated sexually active women who may have a high rate of PID.
Finally, I would like to share with you the difficulty in recruiting university students for Chlamydia screening. The poor response rate has been reported in similar previous studies (Rogstad K E et al 2002; Ivaz S et al 2006). The high refusal rate of the eligible students in your study may impair having a representative study sample that can accurately measure the incident of PID.
Trials
Re: Community-based trail of screening for Chlamydia trachomatis to prevent pelvic inflammatory disease: the POPI (prevention of pelvic infection) trial
19 December 2008
Dear Sir,
I read your study with great interest as we still lack information about the natural history of Chlamydia and PID.
However, your diagnosis of PID relies mainly on the clinical history and I would like to remind you that PID may be symptomatic or asymptomatic and wonder how could you identify asymptomatic PID in your participants. Even symptomatic PID, clinical symptoms and signs lack sensitivity and specificity (the positive predictive value of a clinical diagnosis is 65-90% compared to laparoscopic diagnosis). Also the absence of genital Chlamydia infection does not exclude PID (http://www.bashh.org/documents/118/118.pdf).
Further, although the study information sheet explains the risk, it is challenging to leave women in the control arm with possible asymptomatic genital infection untreated for one year. Similarly, treating women who become symptomatic and infected with Chlamydia in the control arm may eliminate the efforts of reaching the natural history of Chlamydia. Equally, participants may choose to use the barrier method after reading the study information sheet and this may reduce the prevalence of Chlamydia in the study sample, especially the study is targeting university students and excluding uneducated sexually active women who may have a high rate of PID.
Finally, I would like to share with you the difficulty in recruiting university students for Chlamydia screening. The poor response rate has been reported in similar previous studies (Rogstad K E et al 2002; Ivaz S et al 2006). The high refusal rate of the eligible students in your study may impair having a representative study sample that can accurately measure the incident of PID.
Yours sincerely,
Taha Aldeen
Competing interests
None declared