3.1 Study Selection
Our initial search of the literature yielded a total of 454 results. Removal of duplicate articles, title and abstract screening excluded 435 articles. The full texts of the remaining 19 articles were screened and 9 articles were selected for inclusion in this review. A further three articles were sourced from bibliography searches. In total, 12 articles were selected for inclusion in this review; the search strategy is summarised in figure 1.