Figure 1.
The flow diagram illustrates the study selection process across four stages. In Identification, academic articles retrieved from the database total 635, and content retrieved from grey literature search totals 2, giving a total retrieved of 637, after which 6 duplicates relating to academic articles are removed. In Screening, 629 academic articles are screened by abstract and titles, with 499 academic articles excluded. In Eligibility, 130 academic articles are screened by full text, and 68 academic articles are excluded as they do not give further value to the study aim, leaving 62 academic articles whose methods are appraised, with no exclusions. In Included 62 academic articles are included in the quantitative synthesis, with no further exclusions.PRISMA flow diagram detailing the steps of the SLR