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Prevalence of Gram-negative bacteria in ventilator-associated pneumonia in neonatal intensive care units: a systematic review and meta-analysis protocol
  1. Yousef Erfani1,
  2. Arezoo Rasti2,
  3. Leila Janani3
  1. 1Department of Medical Laboratory Sciences, School of Allied Medical Sciences, Tehran University of Medical Sciences, Tehran, Iran
  2. 2Oncopathology Research Center, Iran University of Medical Sciences, Tehran, Iran
  3. 3Department of Biostatistics, School of Public health, Iran University of Medical Sciences, Tehran, Iran
  1. Correspondence to Dr Yousef Erfani; yerfani{at}


Introduction Ventilator-associated pneumonia (VAP) is a common and potentially lethal problem among mechanically ventilated neonates in neonatal intensive care units (NICUs). The main pathogenic bacteria of VAP in NICUs are Gram-negative pathogens, which show a general decline in sensitivities to commonly used antibiotics, but their true prevalence is not known.

Methods and analysis We aim to provide a systematic review of studies measuring the prevalence of Gram-negative bacteria in VAP in NICUs. We will search PubMed, SCOPUS, EMBASE and the ISI Web of Science, as well as the Google Scholar search engine with no restriction on language. Full copies of articles will be identified by a defined search strategy and will be considered for inclusion against predefined criteria. Study selection and data extraction will be performed by 2 independent reviewers. Statistical analysis will include the identification of data sources and documentation of estimates, as well as the application of the random-effects and fixed-effects meta-analysis models. This will allow us to aggregate prevalence estimates and account for between-study variability in calculating the overall pooled estimates and 95% CI for the prevalence of Gram-negative bacteria in VAP in NICUs. Heterogeneity will be evaluated using the I2 and χ2 statistical tests to determine the extent of variation in effect estimates due to heterogeneity rather than chance. Publication bias and data synthesis will be assessed by funnel plots and Begg's and Egger's tests using STATA software V.13. This systematic review protocol was prepared according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses Protocols (PRISMA-P) 2015 Statement.

Ethics and dissemination No ethical issues are predicted. These findings will be published in a peer-reviewed journal and presented at national and international conferences.

Trial registration number CRD42016036048.

  • Systematic Review
  • Ventilator Associated Pneumonia
  • NICU
  • Gram Negative bacteria

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  • Contributors YE, AR and LJ contributed to the concept and study design. AR and LJ developed the search strategies and contributed to the implementation and analysis of the studies. AR contributed to the initial drafting and critical revision and approved the manuscript for submission. AR and LJ revised the manuscript. YE and LJ will also screen potential studies, extract data and assess their quality.

  • Competing interests None declared.

  • Provenance and peer review Not commissioned; externally peer reviewed.

  • Data sharing statement All recorded data from the data extraction process will be available on request to the extent that it is not included in the systematic review article.

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