This protocol has been written according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocol (PRISMA-P, 2015) (Moher et al., 2015).
Eligibility Criteria
The studies that reported the prevalence of Staphylococcus species in the working environment, personnel, and equipment used in the operating room will be included in this study. The articles conducted across the world and written in the English language that reported the quantitative outcomes will be included in this study.
The studies did not report the prevalence of Staphylococcus species, were not conducted in the operating room, and not reported the quantitative outcome will be excluded from this study. Similarly, the articles with inadequate information, editorial reports, short communication and will be excluded from this study.
Data sources and search strategy
The literature search will be carried out by using nine electronic databases and indexing services without any date limit. The MEDLINE, Embase, Psych INFO, PubMed, Scopus, Web of Science, google scholar, Science Direct, and CINAHL databases will be used as major data sources. Whereas, grey literature will be used as supplementary data sources. Keywords and Medical Subject Headings (MeSH) regarding Operation room and pathogen will be used. Examples of search terms include Bacteri* pathogen, microb* contamination, Staphylococcus aureus, S. aureus, methicillin resistant Staphylococcus aureus, antimicrobial resistance, antimicrobial susceptibility, multidrug resistance, operat* room, and operat* theater. Boolean operation (AND, OR, and NOT) will be used to combine these terms in varying ways to identify relevant studies. Search strategies will be customized to suit each database. A draft of the PubMed search strategy is presented in Supplementary material I. The reference lists of all relevant articles will be manually searched to identify any studies missed by electronic database searching.
Study selection
The records obtained from each database will be merged in Endnote X9 (Thomson Reuters, USA), and duplicates will be removed (Rathbone et al., 2015). Studies obtained through the search strategy will be screened by two independent reviewers according to the inclusion and exclusion criteria. This will be done at two stages; stage one, the reviewers will evaluate the title and abstract of each article and at the second stage, the full text of all eligible studies will be retrieved. If a reviewer is unsure about a study’s eligibility at the first stage, a full-text evaluation will be conducted. Also, if there is any disagreement at these two stages, it will be resolved by consensus and, if unresolved, a third reviewer will be consulted. The degree of agreement between both reviewers will be measured utilizing Cohen’s kappa (Cohen, 1960) and a minimum κ value of 0.75 will be taken to represent high agreement.
Data extraction
Information extraction will be done by two authors (EM and DA) under the supervision of the other two authors (YT and KB) using a standardized data extraction spreadsheet prepared in Microsoft Excel; study characteristics (study area, first author, year of publication), Methods (study design, sample source, sample type, sample size), and outcome of interests (positive samples for Staphylococcus spp. and resistant profile positive samples for isolates) will be extracted. If information is missing, or further information is needed the authors will be contacted by E-mail. If authors do not reply until the last manuscript draft, the article will be discarded.
Quality assessment
The quality of studies included will be assessed by the Newcastle-Ottawa scale adapted for cross-sectional studies (Newcastle- Ottawa, 2016) and graded out of 10 points. For ease of assessment, the tool included important indicators categorized into three major sections; the first section assesses the methodological quality of each study and weighs a maximum of five points, the second section considers comparability of the study and takes 2 points, and the remaining section assess outcomes with related statistical analysis. This critical appraisal was conducted to assess the internal and external validity of studies and reduce the risk of biases. Two authors will independently conduct the quality assessment and the mean score of two authors will be taken for final decision and studies with a score greater than or equal to five were included.
Analysis and Data synthesis
We will perform descriptive analysis and report the characteristics of included studies in summary tables and narrative text. The relevant data extracted from selected studies using format prepared in Microsoft Excel will be exported to STATA 16.0 software for analyses of the pooled estimate of outcome measures and subgroup analyses. The primary outcome measure is the prevalence of Staphylococcus spp. isolates in the environment, personnel, and equipment of OR. The pooled prevalence was calculated per Staphylococcus spp. The secondary outcome measure is the antimicrobial resistance status of the Staphylococcus spp. against antimicrobials of different categories. Subgroup analyses will include sources of Staphylococcus spp. in the OR. The prevalence pooled estimates for all pre-specified outcomes of interest will be computed applying random-effects meta-analysis models and reported in forest plots.
Assessment of heterogeneity
The heterogeneity between included studies will be measured using I2 (I Squared test) statistics. The I2 statistic will be calculated to assess inconsistencies in the results of the included studies. The I2 results will be interpreted as follows: unimportant heterogeneity (0%–40%), moderate heterogeneity (30%–60%), substantial heterogeneity (50%–90%), and considerable heterogeneity (75%–100%) (Higgins et al., 2019). Further analysis will be conducted excluding studies with a high risk of bias. To investigate the introduction of publication bias, a random-effects version of Egger’s test will be utilized and visualized through a funnel plot (Sterne et al., 2001).