title: Community-onset sepsis and its public health burden: protocol of a systematic review.
abstract: BACKGROUND
  Sepsis is a life-threatening condition and major contributor of public health and economic burden in the industrialised world. The heterogeneity, absence of more specific definition, and difficulties in accurate diagnosis lead to great variability in the estimates of sepsis incidence. There has been uncertainty regarding the incidence and risk factors attributable to community-onset as opposed to hospital-acquired sepsis. Community-onset sepsis has distinct host characteristics, risk factors, pathogens, and prognosis. A systematic assessment of recent evidence is warranted in light of secular changes in epidemiology, pathogens, and the uncertainties around the incidence and risk factors of community-onset sepsis. This protocol describes a systematic review which aims to synthesise the recent empirical evidence on the incidence and risk factors of community-onset sepsis, severe sepsis, and septic shock in high-income countries.
  
  
  METHODS
  English-language publications of cohort and case-control studies reporting incidence and risk factors of community-onset sepsis will be eligible for inclusion. MEDLINE and Embase databases will be searched from 2002 and onwards. References of relevant publications will be hand-searched. Two reviewers will independently screen titles/abstracts and full texts as well as extract data and appraise the risk of bias of included studies. The data extractions and risk of bias assessments will be cross-checked. Any disagreements will be resolved via consensus. The data on incidence and risk factors of sepsis will be organised and synthesised in text, tables, and forest plots. The evidence will be pooled given sufficient data and degree of similarity across study populations, exposures, and outcomes. The heterogeneity will be assessed through visual inspection of forest plots, Chi-square-based p value, and I (2) statistic. The sources of heterogeneity will be explored via subgroup analysis.
  
  
  CONCLUSIONS
  Timeliness and accuracy of diagnosis of sepsis are both crucial aspects for improving the patient's outcome. The findings of this review will be discussed with a view to better inform future recommendations on improving public-facing campaigns, timely presentation, and diagnosis of sepsis in the community. The review will also discuss gaps in evidence and highlight future research and policy-making avenues for improving public health planning.
  
  
  BACKGROUND
  PROSPERO CRD42015023484.
authors.affiliation: Communicable Disease Control Epidemiology and Evidence; Populations, Evidence and Technologies; Division of Health Sciences; Warwick Medical School, University of Warwick, Coventry, CV4 7AL, UK. a.tsertsvadze.1@warwick.ac.uk.
authors.forename: Alexander
authors.initials: A
authors.lastname: Tsertsvadze
authors.affiliation: Communicable Disease Control Epidemiology and Evidence; Populations, Evidence and Technologies; Division of Health Sciences; Warwick Medical School, University of Warwick, Coventry, CV4 7AL, UK. P.L.Royle@warwick.ac.uk.
authors.forename: Pam
authors.initials: P
authors.lastname: Royle
authors.affiliation: Communicable Disease Control Epidemiology and Evidence; Populations, Evidence and Technologies; Division of Health Sciences; Warwick Medical School, University of Warwick, Coventry, CV4 7AL, UK. N.D.McCarthy@warwick.ac.uk.
authors.forename: Noel
authors.initials: N
authors.lastname: McCarthy
mesh_terms: D017714:Community-Acquired Infections / Q000453:epidemiology* / Q000382:microbiology*; D019049:Developed Countries; D006801:Humans; D015994:Incidence; D011634:Public Health; D012107:Research Design; D012307:Risk Factors; D018805:Sepsis / Q000453:epidemiology* / Q000382:microbiology*; D000078202:Systematic Reviews as Topic