], for example, the delivery of a discrete education program, school curriculum or policy change, changes to a school’s social-emotional or physical environment, or school staff professional development training.We defined anxiety and/or depression as any combination of thoughts, feelings, and behaviours associated with depression and anxiety across the continuum of experience that are persistent, pervasive and cause difficulties in daily life .
Study quality assessment was conducted independently by one researcher with extensive experience in conducting study quality assessments and checked by a second researcher using National Institute of Health tools appropriate for the study design [], namely the Quality assessment tool for observational and cross-sectional studies or the Quality assessment of controlled intervention studies tool.