Figure 4
The flowchart illustrates the process of forward and backward snowballing based on the PRISMA template. It begins with records identified from other methods, totaling 797, which include 230 from backward snowballing and 567 from forward snowballing. Records removed before screening amount to 409, including 244 duplicate records and 165 filtered records. The remaining 388 records are screened, with 59 from backward snowballing and 329 from forward snowballing. Records excluded total 381, with 57 from backward snowballing and 324 from forward snowballing. Reports sought for retrieval are 7, with 2 from backward snowballing and 5 from forward snowballing. One report is not retrieved from forward snowballing. Reports assessed for eligibility are 6, with 2 from backward snowballing and 4 from forward snowballing. Reports excluded are 2, both from forward snowballing. Finally, studies included in the review are 4, with 2 from backward snowballing and 2 from forward snowballing.Search process of snowballing based on PRISMA template. Source: Authors’ own work