Objectives
This is a protocol for a Cochrane Review (intervention). The objectives are as follows:
To assess the benefits and harms of surgical or radiological intervention in addition to broad‐spectrum intravenous antibiotics, compared to broad‐spectrum antibiotics alone, for the treatment of radiologically proven tubo‐ovarian abscesses in non‐pregnant adults.
Background
Description of the condition
Tubo‐ovarian abscess (TOA) is a pathological inflammatory collection involving one or both adnexae (fallopian tube, ovary, or both)[1]. TOAs are typically the result of ascending polymicrobial infection from the lower genital tract, most commonly involving anaerobic organisms such as Escherichia coli, Bacteroides fragilis, and Peptostreptococcus species [2, 3, 4, 5]. TOA may also arise as a complication of pelvic inflammatory disease (PID) due to sexually transmitted pathogens, including Chlamydia trachomatis and Neisseria gonorrhoeae [2, 5, 6].
Risk factors for TOA include a history of PID, multiple sexual partners, intrauterine device (IUD) use, recent gynaecological instrumentation, and immunosuppression [5, 7, 8]. While TOA can occur in reproductive‐aged women, it is increasingly recognised in perimenopausal and postmenopausal women [5].
Although the condition can be suspected based on clinical history and examination findings, a diagnosis can only be made via radiological imaging (usually ultrasound (USS), computerised tomography (CT) scan) or direct visualisation during surgery [1, 2, 7].
Recent published estimates of the prevalence of TOA are limited, and would be expected to vary depending on underlying risk factors in a given population. The global burden of PID in 2019 was estimated at 9536 cases per 100,000 people per year [9], 10% to 30% of whom could be expected to have TOA [2].
Correct treatment for TOA is important, because complications of TOA can be life‐threatening (due to rupture and sepsis), or lead to long‐term morbidity (recurrence, infertility, ectopic pregnancy, and chronic pelvic pain) [1, 7, 10].
Description of the intervention and how it might work
First‐line management of TOA is the administration of medical therapy, most commonly broad‐spectrum intravenous antibiotics (antibiotics that cover gram‐positive, gram‐negative, anaerobic, and aerobic bacteria). Interventional drainage or surgical removal are available interventions used in addition to broad‐spectrum intravenous antibiotics to reduce the burden of infection [1, 2, 6]. These additional interventions can be categorised under radiological drainage (CT‐ or USS‐guided) or surgical interventions (minimal access, laparotomy, or colpotomy approach).
For those who respond to antibiotic treatment alone, the morbidity associated with surgery or anaesthesia for additional interventions can be avoided. However, it remains unclear whether adding surgical or procedural interventions provides an overall benefit in the management of TOA. Early intervention on an inflammatory mass in an unwell patient may increase morbidity due to risks associated with both anaesthesia and the procedure itself. While avoiding surgery may reduce short‐term morbidity, it may allow the inflammatory mass to persist or enlarge, potentially prolonging treatment duration and increasing the risk of clinical deterioration or recurrence [7, 10, 11].
A summary of the benefits and risks for each treatment modality is available in Supplementary material 2.
Why it is important to do this review
1. Tubo‐ovarian abscess is a commonly encountered health problem
TOA is a pathology that is encountered frequently in the hospital setting. Global estimates show a rising incidence of sexually transmitted infections since 2010 [9], which may contribute, as up to 30% of PID cases will have concurrent TOA [2]. In 2016, a report from our public tertiary‐level hospital (serving a population of 500,000 people) estimated there was one admission with a radiologically or surgically proven TOA per week [12]. In our more‐recent retrospective study, we identified 522 admissions with TOA over five years (out of 18,148 gynaecological admissions) [13]. This gives an average of two admissions with TOA per week, which suggests that in our region the incidence of TOA is rising.
2. The circumstances in which additional interventions should be offered and the short‐ and long‐term outcomes associated with their use, compared to medical treatment alone, are unclear
Determining whether there is benefit from additional interventions (beyond broad‐spectrum antibiotics) for a person with a TOA is important, because there is the potential for clinical deterioration (and therefore risk of harm) if additional interventions are not performed in a timely fashion, yet additional interventions carry risk and should not be used unless there is likely to be a benefit.
Current guidance from international groups suggests there is benefit to the use of additional interventions, but does not indicate for whom, or at which stage in the clinical course of TOA, these additional interventions should be used.
British Association for Sexual Health and HIV (BASHH) guidance: "Laparoscopy may help early resolution by dividing adhesions and draining pelvic abscesses, but ultrasound‐guided aspiration of pelvic fluid collections is less invasive" [8].
American College of Obstetricians and Gynaecologists guidance: "The role of image‐guided drainage versus surgical therapy depends on the clinical severity and patient's reproductive stage. Computed tomography and ultrasound‐guided aspiration have been used successfully. Women of reproductive age may benefit from tubo‐ovarian abscess drainage" [7].
Royal College of Obstetricians and Gynaecologists guidance: "Surgical treatment should be considered in severe cases or where there is clear evidence of a pelvic abscess." This guideline was recently archived and directs users to the BASHH guideline.
Without clear guidance, the approach to treatment will be clinician‐dependent, leading to potential bias in care, inefficient or ineffective use of health resources, and has the potential to perpetuate socioeconomic, ethnic, and obesity‐related health inequities. We propose that synthesising the available evidence on the use of additional interventions in TOA will be a useful first step in informing clinical guidance, and identifying evidence gaps to be addressed by future research.
3. Inadequate treatment has short‐ and long‐term consequences for women
Inadequately treated TOAs are associated with longer hospital admissions (potentially increasing healthcare costs), increased short‐term morbidity and mortality, and significant long‐term morbidities such as infertility and chronic pelvic pain. Interventions in addition to antibiotics could reduce some of these risks. This may be particularly important for those with larger masses, bilateral masses, or high fever or inflammatory markers, as observational studies have shown these to be predictive of medical treatment failure [6, 10, 11, 14, 15, 16].
Objectives
To assess the benefits and harms of surgical or radiological intervention in addition to broad‐spectrum intravenous antibiotics, compared to broad‐spectrum antibiotics alone, for the treatment of radiologically proven tubo‐ovarian abscesses in non‐pregnant adults.
Methods
Criteria for considering studies for this review
Types of studies
We will include parallel‐group randomised trials and cluster‐randomised controlled trials. Since cross‐over designs are not applicable to the clinical question of interest, we will not consider these. We will exclude quasi‐randomised controlled trials, such as those in which group allocation is determined by alternation.
We will include studies regardless of their publication status, but will exclude published studies that have subsequently been retracted. We will include publications in English, as well as other languages if a suitable translator is available.
Non‐randomised studies will not be included in this review. We are aware of at least one randomised clinical trial of TOA drainage + antibiotics versus antibiotics alone for the treatment of TOA. We believe that a clinical trial randomising to either antibiotics versus antibiotics plus surgery/radiological drainage is possible and should be conducted, if synthesis of currently published evidence does not provide conclusive results.
Types of participants
We will include participants who are being treated for radiologically detected TOA (magnetic resonance imaging (MRI), CT or USS), in a hospital setting, with intravenous broad‐spectrum antibiotics (regimen will cover both gram‐positive and gram‐negative bacteria) either alone, or in addition to other interventions such as radiological‐guided (CT or USS) drainage or surgical (laparotomy, laparoscopy, colpotomy) drainage.
We will exclude people with the following characteristics.
Children (aged less than 13 years)
Pregnant women
Those with hydrosalpinx only without suspicion of abscess
Those with TOA thought to be reactive to a gastrointestinal cause (e.g. diverticular disease, appendicitis, iatrogenic bowel injury)
TOA diagnosed at the time of surgery (i.e. not by prior radiological imaging)
Known to be immunocompromised
Known to have a congenital pelvic abnormality
Should we identify studies in which only a subset of participants is relevant to this review, we will include such studies if data are available separately for the relevant subset.
Unless the above exclusion criteria are clearly stated in the studies, we will include them. We may also contact the study authors for further details.
Types of interventions
Comparisons will be based on the interventions grouped as follows.
Control group
Broad‐spectrum, intravenous antibiotics received for at least 24 hours without additional intervention (we will include any intravenous antibiotic treatment with known gram‐positive, gram‐negative, anaerobic, and aerobic bacterial cover regardless of dosing).
Intervention groups
Broad‐spectrum intravenous antibiotics received for at least 24 hours (as per control group) AND interventional radiological drainage, including CT‐ and USS‐guided drainage, or other radiological‐guided percutaneous drainage techniques.
Broad‐spectrum intravenous antibiotics received for at least 24 hours (as per control group) AND surgical drainage (including colpotomy, laparoscopy, laparotomy).
We will exclude complementary medicine interventions (e.g. homoeopathy).
Where co‐interventions exist (e.g. radiological drainage is attempted and is then followed by surgical drainage), we will consider the first attempted intervention in addition to intravenous antibiotics and will address the need for further intervention as part of our outcomes.
Outcome measures
Critical outcomes
Short‐term outcomes
Duration of intravenous antibiotic therapy (days)
Duration of hospital stay (days)
Subsequent or repeated additional interventions within the same admission, as reported by trial authors
Mortality rate across study period, as reported by trial authors
Any severe complication (including death, iatrogenic visceral injury, venous thromboembolism, myocardial infarction, anaphylaxis, or any other severe complication) across the study period, as reported by trial authors
Important outcomes
Medium/long‐term outcomes
Recurrence within the study period, as reported by trial authors (readmission to hospital or imaging suggesting recurrence)
Fertility outcomes (core outcome set – viable intrauterine pregnancy confirmed by USS; pregnancy loss (accounting for ectopic pregnancy, miscarriage, stillbirth, and termination of pregnancy); live birth rate) [17] – assessed across the study period, as reported by trial authors. We will aim to assess these outcome measures separately. However, we will prioritise the outcome measure 'any intrauterine pregnancy confirmed by USS' for the summary of findings table in this review, given that the proposed mechanism for infertility following TOA is tubal damage preventing intrauterine pregnancy.
Incidence of chronic pelvic pain is defined as pelvic pain lasting for more than three months, and measured by assessing the number of subsequent hospital admissions related to pelvic pain, or using a validated pain scale, or by recording data as either yes or no for presence or absence, regardless of measure used. We will assess the presence or absence of this across the study period as defined by trial authors.
We anticipate that adequate long‐term follow‐up data may not be available for the fertility and chronic pain outcomes described above, although we feel these outcomes are still important and of relevance to patients. Therefore, we will aim to report these descriptively.
Should we identify studies potentially suitable for review in which none of the above outcomes are reported, we will assess the data for relevant information on unreported relevant outcome measures. Where necessary, we will contact study authors to ascertain if data were collected and request additional data relevant to the above outcome measures. If the data are unavailable or have not been measured, we will exclude the study.
Search methods for identification of studies
We will perform a comprehensive search, with no restrictions on the language of publication or publication status. We plan to do this in consultation with the Cochrane Gynaecology and Fertility Group's Information Specialist.
Electronic searches
We will search the following sources from the inception of each database to present: Cochrane Gynaecology and Fertility Specialised Register (ProCite platform), CENTRAL via the Cochrane Register of Studies Online (CRSO) (Web platform), MEDLINE (Ovid platform), and Embase (Ovid platform). All search strategies are presented in Supplementary material 1.
Other electronic sources we plan to search include trial registers for ongoing and registered trials: US National Institutes of Health Ongoing Trials Register ClinicalTrials.gov (https://www.clinicaltrials.gov), World Health Organization International Clinical Trials Registry Platform (https://apps.who.int/trialsearch), Web of Knowledge (https://wokinfo.com/), OpenGrey (https://www.opengrey.eu/), LILACS (Literaturo Latino Americana e do Ciências da Saúde) database (https://regional.bvsalud.org), PubMed, and Google Scholar.
Searching other resources
We will try to identify other potentially eligible trials or ancillary publications by searching the reference lists of retrieved included trials, reviews, and meta‐analyses identified during the searches. We will consider contacting study authors of included trials to identify any further studies that we may have missed.
We will check PubMed (https://pubmed.ncbi.nlm.nih.gov/) and Retraction Watch (https://retractiondatabase.org/RetractionSearch.aspx?) for any postpublication retractions or expressions of concern affecting eligible studies.
Data collection and analysis
Selection of studies
Two review authors (from HB, CO, KC, AM, JW, MB) will perform an initial screen of titles and abstracts retrieved by the search in Covidence [18], using a hierarchy of exclusion checklist. We will remove duplicated abstracts using the relevant function in Covidence, and by comparing study characteristics during screening and manually removing duplicate studies if identified. Where abstracts are not in English, we will use Google Translate to determine eligibility. We will retrieve the full texts of all potentially eligible studies. Where a potentially eligible study is not in English, we will seek the assistance of a translator. Two review authors will independently examine all full‐text articles for compliance with the inclusion criteria and select studies eligible for inclusion in the review. We will check the references from the studies under consideration for inclusion. We will resolve any disagreements by referral to a third review author, who will not have been one of the two initial authors involved in assessing that study. We will evenly divide the work between us (HB, CO, KC, AM, JW, MB) following the search.
Screening eligible studies for trustworthiness
At least two review authors (from HB, CO, KC, AM, JW, MB) will evaluate all studies meeting our inclusion criteria to select studies that, based on available information, we deem to be sufficiently trustworthy to be included in the analysis.
We will use one of the following screening checklists.
Checklist to assess Trustworthiness in RAndomised Controlled Trials (TRACT checklist) [19]
Cochrane Pregnancy and Childbirth Trustworthiness Screening Tool [20]
We will check Retraction Watch for retraction notices or expressions of concern relating to each study and document this process (https://retractiondatabase.org/RetractionSearch.aspx?). We will exclude any studies that have been retracted or withdrawn, and categorise as 'awaiting classification' any studies that have a published expression of concern or that we assess to be potentially problematic.
Data extraction and management
Two review authors (from HB, CO, KC, AM, JW, MB) will independently extract data from eligible studies using a data extraction form designed by the authors, adapted from Chapter 5 of the Cochrane Handbook for Systematic Reviews of Interventions [21]. We will pilot this form on at least two studies. We will resolve any disagreements by referral to a third review author, who will not have been one of the two initial authors involved in assessing that study. We will evenly divide the work between us (HB, CO, KC, AM, JW, MB) following the search.
We will record the following information.
Article information (author, date, language, author contact details)
Study information (duration, length of follow‐up, attrition/non‐response, sample size, study limitations, funding source)
Population (setting; region(s) and country/countries from which study participants were recruited; study eligibility criteria, including diagnostic criteria; and characteristics of participants at the beginning (or baseline) of the study (e.g. age, sex, comorbidity, socioeconomic status))
Methods (study design, setting, deviations from the study protocol, randomisation/blinding, statistical methods including how cluster randomised trials were dealt with)
Intervention (components, routes of delivery, doses, timing, frequency, intervention protocols, length of intervention, factors relevant to implementation (e.g. staff qualifications, equipment requirements), integrity of interventions (i.e. the degree to which specified procedures or components of the intervention were implemented as planned), description of co‐interventions, definition of 'control' groups (e.g. no intervention, placebo, minimally active comparator, or components of usual care))
Outcomes and time points (those collected and those reported, unit measurements and how outcome measures were defined, any aggregate measures used)
Results (impacts on outcomes and relevant subgroups, summary data, any adverse effects reported and how they were measured)
Required information for GRADE summary of findings table
Where studies have multiple publications, we will collate multiple reports of the same study, so that such studies have a single study ID with multiple references. We will correspond with study investigators for further data on methods, results, or both, as required. We will create a summary of included studies similar to Table 1.
1. Overview of included studies and synthesis table illustrating key characteristics of studies, outcomes, and synthesis, sorted alphabetically.
| Study, country of conduct | Study type | Key details of intervention | Population (sample size: intervention/control) | Outcome domains with available data | Specific outcome measure | Time point of measurement | Synthesis method |
Source: adapted from Pega and colleagues [31].
Risk of bias assessment in included studies
Two review authors (HB, CO) will independently assess risk of bias for each trial using the Excel ROB 2 tool [22] in Review Manager [23], outlined in Chapter 8 of the Cochrane Handbook for Systematic Reviews of Interventions [21]. We will assess the risk of bias for all critical and important outcomes as outlined below. The effect of interest in this review is assignment, and we will estimate this using an intention‐to‐treat analysis as this most closely aligns with our study objectives. Where possible, we will analyse all participants within the intervention groups to which they were originally randomised, regardless of the interventions they actually received, and will include all randomised participants in the analysis regardless of their outcomes.
We will assess the risk of bias for the following outcomes.
Duration of intravenous antibiotic therapy (days)
Duration of hospital stay (days)
Subsequent or repeated additional interventions within the same admission as reported by trial authors
Mortality rate across study period as reported by trial authors
Any severe complication across the study period as reported by trial authors (including death, iatrogenic visceral injury, venous thromboembolism, myocardial infarction, anaphylaxis, or any other severe complication)
Recurrence within the study period as reported by trial authors (readmission to hospital or imaging suggesting recurrence)
The domains of bias that will be addressed are as follows.
Bias arising from the randomisation process, for example, alternate randomisation or other methodology which allows the future knowledge or prediction of assignments.
Bias due to deviation from intended intervention. As the main effect of interest is assignment to the intervention, we will consider there to have been deviations from the intended intervention within a study if they are inconsistent with trial protocol, arise because of the experimental context, or influence the outcome. There are unlikely to be any non‐protocol interventions received by participants that would affect the outcome of interest, but we will reassess this for each included study. We will assess the role of blinding for each included study at the level of participants, carers, and people delivering the interventions.
Bias due to missing outcome data, including methods used to account for missing data within studies. We will consider both the true value of the outcomes for participants with missing data and the likely underlying cause that led to the missing outcome data, and whether these are related, to help us assess the likelihood of bias in this domain.
Bias in measurement of outcome – this will include assessment of whether the method of measuring the outcome is appropriate, whether this method is the same across intervention groups, who is measuring the outcome data and whether they are blind to the intervention assignment, and whether the outcome assessment could be influenced by the knowledge of the intervention received.
Bias in selection of the reported results – we will assess this by obtaining the prespecified analysis intentions for each trial and comparing these to the actual analysis. Where this is not possible, we will assess the methodology section and compare it to the results. We will cross‐compare outcome measures and analyses for all papers relating to a trial.
Authors will utilise signalling questions as outlined by Cochrane to indicate a judgement of 'low risk of bias', 'some concerns', or 'high risk of bias' for each included study, in each of the above domains and then overall. We will exclude from the analysis any studies which are at high risk of bias.
If we encounter cluster‐randomised trials, we will analyse these using the ROB 2 guidance and template specific to cluster‐randomised trials.
We will resolve any disagreement by discussion, or by involving a third review author (MB).
Measures of treatment effect
We will perform statistical analysis in accordance with the guidelines in the Cochrane Handbook for Systematic Reviews of Interventions [21]. We will analyse the data using an intention‐to‐treat model as discussed above.
We will express dichotomous data as the numbers of events in the control and intervention groups of each study and calculate Mantel‐Haenszel odds ratios (OR) with 95% confidence intervals (CI). An increase in the odds of a particular outcome will be displayed graphically in the meta‐analyses to the right of the centre line, and a decrease in the odds of an outcome will be displayed graphically to the left of the centre line.
For continuous data (e.g. length of hospital stay), if all studies report the same outcomes, we will calculate the mean difference (MD) between treatment groups. If similar outcomes are reported on different scales, we will calculate the standardised mean difference (SMD). We will reverse the direction of effect of individual studies, if required, to ensure consistency across trials. We will present 95% CIs for all outcomes.
We will use time‐to‐event data to capture the mortality rate and recurrence rate as reported by the study authors [24].
Unit of analysis issues
The primary analysis will be per woman randomised. If we encounter any cluster‐randomised or multi‐arm trials, we will analyse the data according to the advice set out in Chapter 23 of the Cochrane Handbook for Systematic Reviews of Interventions [25]. For cluster‐randomised trials, we will estimate the intracluster (or intraclass) correlation coefficient (ICC), either by obtaining this information from the trial data or by using an external estimate based on a similar study. We will obtain statistical support to assist us with this process. For multi‐arm studies, our approach will be to combine groups to create a single pair‐wise comparison, and we will seek statistical support with regard to the correct approach for assessing heterogeneity in this instance, depending on the specific data.
We may also choose to summarise data that did not allow valid analysis (e.g. descriptive data) in additional tables and will exclude this from meta‐analysis.
Dealing with missing data
Two review authors will independently assess the included studies for the number of women lost to follow‐up, and exclusions from analysis after randomisation (dropouts).
We will follow the five general recommendations for dealing with missing data in Cochrane reviews [26], as follows.
Whenever possible, contact the original investigators to request missing data.
Make explicit the assumptions of any methods used to address missing data: for example, that the data are assumed missing at random, or that missing values were assumed to have a particular value, such as a poor outcome.
Use the RoB 2 tool to assess risk of bias due to missing outcome data.
Perform sensitivity analyses to assess how sensitive results are to reasonable changes in the assumptions that are made.
Address the potential impact of missing data on the findings of the review in the Discussion section.
Reporting bias assessment
If we find 10 or more trials for the primary outcomes, we plan to use a funnel plot to explore the possibility of small‐trial effects. We will assess asymmetry in this case using the Egger test [27], as well as visual inspection of the funnel plot. Where we are concerned that small‐trial effects are influencing the results of our meta‐analysis, we will perform a sensitivity analysis to explore this further.
Synthesis methods
We will present data from all eligible studies in the following comparisons.
Broad‐spectrum intravenous antibiotics received for at least 24 hours without additional intervention (including any antibiotic treatment with gram‐positive and gram‐negative, anaerobic and aerobic bacterial cover) versus broad‐spectrum intravenous antibiotics (as defined in comparison group) received for at least 24 hours plus interventional radiological drainage (including CT‐ and USS‐guided drainage, percutaneous drainage techniques).
Broad‐spectrum intravenous antibiotics (as defined previously) received for at least 24 hours without additional intervention versus broad‐spectrum intravenous antibiotics (as defined previously) received for at least 24 hours plus surgical drainage or removal of abscess (including colpotomy, laparoscopy, laparotomy).
We plan to use a fixed‐effect model to calculate a pooled estimate of effect in meta‐analyses if there is sufficient clinical and methodological similarity between the identified studies. There is likely to be some heterogeneity due to different approaches to intervention (e.g. interventional drainage versus surgery). We plan to perform a subgroup analysis to explain this further, and use strata to display data on different subcategories within the above comparisons. For example, different types of surgical drainage.
We will utilise other statistical synthesis methods where we are unable to complete a meta‐analysis for reasons such as limited evidence; incompletely reported outcome/effect estimates; different effect measures used across studies; and bias in the evidence. Depending on the reason we are unable to complete meta‐analyses, we may summarise effect estimates, combine P values, or use vote counting based on direction of effect. We will use the SWiM guidance to structure our approach to these situations [28].
Investigation of heterogeneity and subgroup analysis
We will utilise the Chi2 test to assess for heterogeneity.
Where data are available (at least 10 studies), we will present data in the following subgroups to investigate whether there is a subset of participants for whom interventions in addition to intravenous antibiotics provide greater benefit than intravenous antibiotics alone.
Participants with bilateral masses versus unilateral masses
Participants with masses greater than 5 cm versus 5 cm or less
Surgical drainage of abscess versus complete removal
Laparoscopic surgical approach versus open approach
Equity‐related assessment
We do not plan to investigate health equity in this review because the scope of this review is to assess available randomised controlled trial evidence, and our author team does not have particular expertise in conducting equity‐related assessments.
Sensitivity analysis
We plan to perform the following sensitivity analyses.
Exclude studies with a general judgement of high or unclear risk of bias.
Exclude studies with a data loss of more than 20%, as bias increases with greater amounts of missing data [29].
Certainty of the evidence assessment
We will use the GRADE approach to assess the critical and important outcomes in our review [30], and will use the overall RoB 2 judgements to do this.
The following outcomes will be included in the summary of findings tables.
Duration of intravenous antibiotic therapy (days)
Duration of hospital stay (days)
Subsequent or repeated additional interventions within the same admission, as reported by trial authors
Mortality rate across study period, as reported by trial authors
Any severe complication (including death, iatrogenic visceral injury, venous thromboembolism, myocardial infarction, anaphylaxis, or any other severe complication) within the study period, as reported by trial authors
Recurrence within the study period, as reported by trial authors (readmission to hospital or imaging suggesting recurrence)
We will report the following comparisons in two separate summary of findings tables.
Broad‐spectrum intravenous antibiotics received for at least 24 hours without additional intervention (including any antibiotic treatment with anaerobic and aerobic bacterial cover) versus broad‐spectrum intravenous antibiotics received for at least 24 hours plus interventional radiological drainage (including CT‐ and USS‐guided drainage, percutaneous drainage techniques).
Broad‐spectrum intravenous antibiotics received for at least 24 hours without additional intervention (including any antibiotic treatment with anaerobic and aerobic bacterial cover) versus broad‐spectrum intravenous antibiotics received for at least 24 hours plus surgical drainage (including colpotomy, laparoscopy, laparotomy).
Two review authors (HB and CO) will independently assess the certainty of evidence as high, moderate, low, or very low [21].
We will assess each of the following domains, resolving any disagreements by consulting with a third review author (MB or AM).
Risk of bias
Inconsistency
Indirectness
Insufficient precision
Publication bias
Consumer involvement
Consumers were not involved in this protocol and will not be involved in the review due to limited resources, although the review authors plan to use core outcome sets for the review's outcomes, which were developed with consumer involvement.
Supporting Information
Supplementary materials are available with the online version of this article: 10.1002/14651858.CD016056.
Supplementary materials are published alongside the article and contain additional data and information that support or enhance the article. Supplementary materials may not be subject to the same editorial scrutiny as the content of the article and Cochrane has not copyedited, typeset or proofread these materials. The material in these sections has been supplied by the author(s) for publication under a Licence for Publication and the author(s) are solely responsible for the material. Cochrane accordingly gives no representations or warranties of any kind in relation to, and accepts no liability for any reliance on or use of, such material.
Supplementary material 1 Search strategies
Supplementary material 2 Benefits and Risks of treatment modalities for TOA
New
Additional information
Acknowledgements
Helen Nagels helped develop the original protocol and Mariam Showell assisted with data search and extraction.
Editorial and peer‐reviewer contributions
Cochrane Gynaecology and Fertility supported the authors in the development of this protocol.
The following people conducted the editorial process for this article.
Sign‐off Editor (final editorial decision): Madelon van Wely, Amsterdam UMC
Managing Editor (selected peer reviewers, provided editorial guidance to authors, edited the article): Hannah Payne, Cochrane Central Editorial Service
Editorial Assistant (conducted editorial policy checks, collated peer‐reviewer comments and supported editorial team): Cynthia Stafford, Cochrane Central Editorial Service
Copy Editor (copy editing and production): Andrea Takeda, Cochrane Central Production Service
Peer reviewers (provided comments and recommended an editorial decision): Jennifer Hilgart, Cochrane (methods review), Jo Platt, Central Editorial Information Specialist (search review). One additional peer reviewer provided clinical/content peer review but chose not to be publicly acknowledged.
Contributions of authors
HB and CO: protocol development.
AM, JW, MB, and KC: review of the protocol.
We anticipate the following contributions from authors during the completion of the systematic review.
HB: co‐lead (search and study selection, data extraction, syntheses, risk of bias and GRADE assessment, data interpretation and analysis, write‐up).
MB: assistance with search and selection of studies, collection of data for review, risk of bias and GRADE assessment, and review of manuscript.
JW: assistance with search and selection of studies, collection of data for review, and review of manuscript.
KC: assistance with search and selection of studies, collection of data for review, and review of manuscript.
AM: assistance with search and selection of studies, collection of data for review, GRADE assessment, and review of manuscript.
CO: co‐lead (search and study selection, data extraction, syntheses, risk of bias and GRADE assessment, data interpretation and analysis, write‐up).
Declarations of interest
HB: none.
MR: none.
JW: none.
KC: none.
AM: none.
CO: none.
Sources of support
Internal sources
-
The University of Auckland, New Zealand
Author salary
External sources
-
None, Other
No external sources of support received.
Registration and protocol
Cochrane approved the proposal for this review in October 2023.
Data, code and other materials
Data sharing is not applicable to this article as it is a protocol, so no datasets were generated or analysed.
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Associated Data
This section collects any data citations, data availability statements, or supplementary materials included in this article.
Supplementary Materials
Supplementary material 1 Search strategies
Supplementary material 2 Benefits and Risks of treatment modalities for TOA
Data Availability Statement
Data sharing is not applicable to this article as it is a protocol, so no datasets were generated or analysed.