Arredondo 1997

Methods	Randomized, double‐blind, comparative study.
Participants	Inclusion criteria: women aged 18‐55 years with clinical diagnosis of mild or moderate PID, as confirmed by laparoscopy graded according to the methods of Hager and colleagues (Hager 1983); and Soper (Soper 1991). Exclusion criteria: observable pelvic mass; presented with laparoscopic evidence of severe PID; pregnant or breastfeeding; allergic to clindamycin, ciprofloxacin, ceftriaxone, or doxycycline; required other antibiotic therapy for non‐protocol reasons; had had pelvic or abdominal surgery in the 30 days prior to admission (except emergency exploratory laparoscopy resulting in a primary diagnosis of PID that did not require pelvic cleanup); had concomitant disease that could have affected the evaluation of response to protocol therapy (such as inflammatory bowel disease or significant renal or hepatic disease); had a history of colitis; were known to have frequent sexual contacts with multiple partners; were seropositive for syphilis; had severe medical condition(s) (e.g. neoplasms or haematological malignancy); had taken ≥ 2 antibiotics within 72 h before evaluation for enrolment in the study; had received any investigational drug 30 days before evaluation for enrolment; or had been previously enrolled in the study. Number of women randomized: 69 in each group. Number of women analyzed: .69 in each group Number of withdrawals/exclusions/loss to follow‐up and reasons: 2 in the clindamycin+ciprofloxacin group; 1 chose to discontinue because she was asymptomatic and 1 withdrew because of a side effect. In the ceftriaxone+doxycycline group, 1 withdrew because of a side effect, 1 was lost to follow‐up and 1 was withdrawn because of receiving additional antibiotic treatment for syphilis after initiation of study medication. Number of centres: 6; Chile (1 centre), Peru (2 centres), Colombia (2 centres), and Mexico (1 centre). Age (mean) (years): group A: 28.9; group B: 30.7. Country: Mexico
Interventions	Group A: clindamycin 300 mg (2 capsules 3 times daily) + ciprofloxacin (250 mg, 1 tablet twice daily) for 14 days and placebo IM (for an equivalent of 1 dose of ceftriaxone). Group B: ceftriaxone 250 mg IM (as a single dose) + doxycycline 100 mg (1 capsule twice daily) and placebo (2 capsules 3 times daily for equivalent doses of clindamycin) for 14 days.
Outcomes	Clinical cure defined by the absence of, or minimal, pelvic tenderness, temperature < 37.5 °C, and a WBC count of 10,000/mm3, if a minimum of 4 days of treatment had been completed. Clinical improvement defined as resolution of 2 of these 3 symptoms. Failure when 1 of the following circumstances was noted after at least 48 h of protocol therapy: signs and symptoms remained unchanged or worsened (during the first 72 h of therapy). Microbiological cure defined as eradication of N gonorrhoeae or C trachomatis (or both) from clinically cured women. Failure defined as persistence of 1 or both of these 2 organisms or, in the case of clinical improvement or failure, the presence of endocervical pathogens. Superinfection defined as the isolation of ≥ 1 new pathogens. Adverse effects leading to discontinuation of treatment.
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	All eligible women randomized to 1 of the treatment groups.
Allocation concealment (selection bias)	Unclear risk	Not stated.
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Placebo medication was added as necessary to complete the double‐blind design. All oral medication was encapsulated to ensure blinding.
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Placebo medication was added as necessary to complete the double‐blind design. All oral medication was encapsulated to ensure blinding.
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Not stated.
Selective reporting (reporting bias)	Unclear risk	No trial protocol found.
Other bias	Unclear risk	Not stated.