RT Journal Article SR Electronic T1 Randomised controlled trial of screening for Chlamydia trachomatis to prevent pelvic inflammatory disease: the POPI (prevention of pelvic infection) trial JF Journal of Family Planning and Reproductive Health Care JO J Fam Plann Reprod Health Care FD British Medical Journal Publishing Group SP 21 OP 21 DO 10.1136/jfprhc.2010.0010 VO 37 IS 1 A1 Paddy Horner YR 2011 UL http://jfprhc.bmj.com/content/37/1/21.abstract AB