• SYSTEMATIC REVIEWS
• GUIDELINE DEVELOPMENT
• CLINICAL TRIALS

The systematic review by Savaris and colleagues1 is important for two reasons. First is the review of the treatment of pelvic inflammatory disease (PID), a common condition for which the management is contentious, driven by traditions and not necessarily evidence-based. Second, the publication of this abridged review will help to strengthen links between the Sexually Transmitted Infections Cochrane Review Group (STICRG, https://sti.cochrane.org/)2 and the journal to bring important clinical evidence from the Cochrane Library closer to our readers and other practitioners.

The systematic review of antibiotic therapy for PID, which included 37 randomised controlled trials, makes for interesting reading, particularly about the use of nitroimidazoles.1 The evidence suggests that the addition of metronidazole to any of the evaluated regimens does not improve clinical cure for either mild to moderate PID (5 trials, 1383 women) or severe PID (11 trials, 2427 women).1 The authors judged the quality of the evidence as moderate rather than high, presumably because of missing information from the trial reports (figures 1 and 2 in the published paper).1 The authors suggest that other antibiotics in the regimens tested must have provided enough anaerobic cover. Metronidazole is widely recommended to treat vaginal anaerobic bacteria that are often found in women with PID, but whose role in the upper genital tract infection is still not proven.3 Regimens that do not contain metronidazole could improve adherence to antibiotic regimens and reduce concern about antimicrobial resistance, given that nitroimidazoles are the only class of drug recommended for treatment of Trichomonas vaginalis. Clinical guideline developers should take these findings into consideration. But a quick look at the 2018 BASHH and HIV guideline for the management of PID shows that the review evidence has not filtered through. The guideline gives the highest (grade 1A) recommendation for outpatient and inpatient regimens containing metronidazole.4 The search for the systematic review ended in July 2016, so new trials with improved reporting of results might provide more certainty when the authors update the Cochrane review in 2020.

The Cochrane Collaboration benefits from the copublication of systematic reviews in journals like ours because the abridged version reaches a wider audience that includes the end users. Cochrane Collaboration systematic reviews must adhere to high standards of completeness, methods to reduce the risk of bias, transparency and reporting. These requirements can make the full review very long and difficult to understand for people who are not familiar with their structure and language. An abridged review can highlight the most salient findings from a review and put them into context for a specific audience. The full Cochrane Library review provides all the details, although access is restricted to those with subscriptions or exemptions. Guideline development groups should identify and make use of the full Cochrane review, but an abridged version can also draw attention to topics that are of current relevance to clinical practice.

Sexually Transmitted Infections will consider future copublication of reviews from the STICRG and other relevant Cochrane review groups. Box 1 provides some tips for authors who want to copublish a Cochrane review, based on the Cochrane Community’s editorial and publishing policy5 and our experience in editing this submission. In the meantime, the STICRG encourages clinicians and researchers to get involved in the STICRG. The STICRG editorial office is at the National University of Colombia, Bogotà, Colombia, and the group is a satellite of the Cochrane Gynaecology and Fertility Group. Look out for Cochrane Collaboration training courses (https://training.cochrane.org/) online, webinars, workshops and long courses, and get in touch with our managing editor, Olga Gomez (cochranestieditorialoffice@gmail.com), who can put you in touch with review authors. Help to make sure that the management of STIs is based on the best possible evidence.