Soper 1988

Methods	Randomized controlled trial.
Participants	Inclusion criteria: written informed consent; met criteria for diagnosis of PID with the following: lower abdominal pain and bilateral adnexal tenderness on bimanual pelvic examination; microscopy of a wet mount of the vaginal contents revealing marked increase in the number of leukocytes (i.e. leukocytes outnumbered all other cellular elements in the smear); ≥ 2 of the following: temperature > 38 °C, leukocytosis (> 11,000/mm3), purulent material from the peritoneal cavity by culdocentesis, inflammatory complex on bimanual examination or sonography, ESR > 20 mm/h; uncomplicated salpingitis limited to tube(s) or ovary(ies) (or both) without pelvic peritonitis; complicated (inflammatory mass or abscess involving tube(s) or ovary(ies) (or both) with or without pelvic peritonitis. Exclusion criteria: pregnant; history of allergy to 1 of study drugs. Number of women randomized: 62; 31 in each group. Number of women analyzed: 62; 31 in each group. Number of withdrawals/exclusions/loss to follow‐up and reasons: 0 reported as lost to follow‐up. Number of centres: 1. Age (mean ± SD) (years): group A: 23.4 ± 5.8; group B: 21.9 ± 3.7. Country: US.
Interventions	Group A: cefoxitin 2 g IV every 6 h + doxycycline 100 mg IV every 12 h. Women discharged with doxycycline 100 mg PO twice daily to complete a 10‐day course. Group B: clindamycin 600 mg IV every 6 h + amikacin 7.5 mg/kg IV every 12 h. Women discharged with clindamycin 300 mg PO 4 times daily to complete a 10‐day course.
Outcomes	Primary outcome: clinical failure: persistence of fever (> 38 °C), elevated WBC (> 11,000/mm3), moderate‐severe pelvic organ tenderness despite 96 h of antibiotic therapy, need of laparotomy. Secondary outcome: length of hospital stay.
Notes	Ethical approval: not stated. Informed consent: yes, enrolled after obtaining informed consent according to guidelines of the Human Research Committee. Source of funding: not stated, and no conflicts of interest reported.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Women admitted to hospital and assigned randomly in a double‐blind fashion, to 1 of 2 treatment regimens by sealed envelope, generated from a table of random numbers.
Allocation concealment (selection bias)	Unclear risk	Allocation reported to have taken place in sealed envelopes, but it was not reported who distributed them.
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Not stated who was blinded.
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Not stated who was blinded.
Incomplete outcome data (attrition bias) All outcomes	Low risk	All women randomized were analyzed.
Selective reporting (reporting bias)	Unclear risk	No study protocol found.
Other bias	High risk	Significant baseline imbalances between the 2 groups. Age, infertility, and severity of pain prior to this study was significant lower in group B (clindamycin/gentamicin).