Figure 1
The prisma flow diagram shows a vertical process arranged from top to bottom with side exclusions on the right and phase labels on the left. On the far left, three vertical rectangular boxes label the phases “Identification”, “Screening”, and “Included” from top to bottom. At the top center under “Identification”, a large rectangular box reads “Records identified from Scopus, Web of Science, Google Scholar, ScienceDirect, Taylor & Francis Online, and SpringerLink: (n equals 102)”. A double-headed horizontal arrow points right to a box that reads “Records removed before screening: Duplicate records removed (n equals 23)”. From the first central box under “Screening”, a vertical downward arrow leads to a box reading “Records screened: 79 studies underwent an initial manual screening against exclusion criteria E A 1 and E A 2 (n equals 79)”. A double-headed horizontal arrow points right from this box to a box reading “Records excluded: Elimination of studies that did not meet the basic eligibility requirements (n equals 44)”. A vertical downward arrow continues under “Screening” to a box reading “Studies selected for full-text evaluation (n equals 35)”. A double-headed horizontal arrow points right to a box reading “Studies excluded based on criteria E A 5 and E A 6 (n equals 16)”. A vertical downward arrow continues under “Screening” to a box reading “Papers found suitable (n equals 19)”. A double-headed horizontal arrow points right to a box reading “Further Inclusion of studies snowballing: (n equals 7)”. From this right-side box, a vertical downward arrow leads to another box reading “Exclusion based on further manual review (n equals 2)”. From “Papers found suitable (n equals 19)”, a vertical downward arrow leads to the final bottom center box under “Included” reading “Studies included in review (n equals 24)”.Refinement and inclusion of studies in research process