From: Moher D, Liberati A, Tetzlaff J, Altman DG, The PRISMA Group (2009). Pref erred Reporting Items f or Systematic Review s and Meta-
Analyses: The PRISMA Statement. PLoS Med 6(7): e1000097. doi:10.1371/journal.pmed1000097
PRISMA 2009 Flow Diagram
Records identified through
database searching
(n = )
Screening
Included
Eligibility
Identification
Additional records identified
through other sources
(n = )
Records after duplicates removed
(n = )
Records screened
(n = )
Records excluded
(n = )
Full-text articles assessed
for eligibility
(n = )
Full-text articles excluded,
with reasons
(n = )
Studies included in
qualitative synthesis
(n = )
Studies included in
quantitative synthesis
(meta-analysis)
(n = )