The primary reasons for these limitations were language proficiency of the team and time needed to complete the review. [...] The review team did not feel that these idiosyncrasies in the studies selected would bias the results of our assessment of agreement between the QC reviewer and the team. [...] The level of agreement between the reviewers and the QC reviewer was examined for exclusion of studies. [...] Institute for Work & Health Table 4: Data extraction items 1. State the research question/objective 2. State the primary hypothesis 3. State additional hypotheses not listed in question #2 4. Write the last name of the first author and the year of publication 5. List the jurisdiction where the study was completed 6. What industry/sector was the study conducted in? [...] Such a high level of heterogeneity required us to use a synthesis approach adapted from Slavin and others (Slavin 1995, Franche 2004, Côté 2001) known as “best evidence synthesis.” The best evidence synthesis approach used here considers the quality of the articles, the quantity of articles and the consistency of the findings among the articles (Table 5).