Ietje Perfors

52 Chapter 3 Data extraction and management To determine relevance, the records were divided and screened on title and abstract by two single reviewers (IP,JB) and discussed with three additional reviewers in case of doubt (AM,CH and JB or IP). Two authors (IP,JB) performed full-text screening. Disagreements on eligibility were resolved in group discussion with researchers and clinicians (IP,JB,AM,CH). A meta-analysis was planned to be conducted if possible. Patient and public involvement Patients and public were not involved in the design of the current study. Quality assessment Risk of bias for individual studies was scored by two authors (JB,IP) with the risk of bias criteria from the “Effective Practice and Organisation of Care Group (EPOC), which is a Cochrane review group. 13 In case outcomes of homogeneous study designs could be merged we rated the body of the evidence following the Grades of Recommendation, Assessment, Development and Evaluation approach (GRADE) 14 from the Cochrane collaboration. This systematic review is reported following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2009 checklist. 15