Tyson 2009.

Methods	Cluster‐randomized trial
Participants	405 teachers in 63 primary schools in Western Australia Only data for teachers (n = 96) who completed the affective wellbeing scales at all 3 time points have been reported, without ITT analysis. Considering that this study was a three‐arm trial, we deemed only one of the intervention groups to contain an organisational intervention relevant to this review. Thus the total number of participants analysed for this review was 59 teachers in 43 schools. The intervention group consisted of 26 teachers in 22 schools, and the control group consisted of 33 teachers in 21 schools. The individual‐level intervention excluded from this review consisted of 37 teachers in 20 schools.
Interventions	The Aussie Optimism programme is a universal, mental‐health promotion programme, delivered by teachers and aimed at preventing anxiety and depression in children and adolescents. The aim of the study is to assess whether the programme has a secondary positive impact on teachers’ job‐related affective wellbeing. The study contains 1 control and 2 intervention groups: 1‐ Teacher training in Aussie Optimism 2‐ Teacher training in Aussie Optimism along with coaching for the duration of the study 3‐ Usual care‐ implementing the regular Western Australian Health Education Curriculum
Outcomes	Job‐related Anxiety‐Contentment Scale, Job‐related Depression‐Enthusiasm Scale Surveys conducted at baseline, and subsequently 12 months and 24 months post intervention
Notes	The main purpose of this study was mental‐health promotion in children; job‐related affective wellbeing in teachers was investigated as a secondary outcome. Date of the intervention: Not reported Funding: Not reported Conflict of interest: Unknown
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Schools were randomly allocated to the 3 study groups, but no mention of method of sequence generation
Allocation concealment (selection bias)	Unclear risk	Not reported
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Not reported, not applicable
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Not reported
Incomplete outcome data (attrition bias) All outcomes	High risk	Only data for teachers (n = 96) who completed the affective wellbeing scales at all 3 time points have been reported, without ITT analysis
Selective reporting (reporting bias)	High risk	ITT analysis for 405 teachers who participated in the study showed no significant results and was not reported
Recruitment bias	Unclear risk	Not reported
Baseline imbalance	Unclear risk	Not reported
Incorrect analysis	High risk	Clustering of teachers within schools was accounted for. However, the reported analysis was for teachers who completed the surveys, and ITT analysis was not reported
Other bias	High risk	Although mean differences did not show any significant effects, the authors utilised hierarchical regression analysis to claim significant effects on job‐related anxiety at 24‐month assessment and job‐related depression at both 12‐ and 24‐month assessments compared to the control group