Comparison 2. Anger/conflict response interventions versus no intervention by type of school.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 Difference in aggression scale score or observed aggression by type of school (post test)	18	943	SMD (Random, 95% CI)	‐0.39 [‐0.61, ‐0.16]
1.1 Primary school	10	546	SMD (Random, 95% CI)	‐0.46 [‐0.78, ‐0.15]
1.2 Secondary school	8	397	SMD (Random, 95% CI)	‐0.29 [‐0.64, 0.06]
2 Difference in aggression scale score or observed violence by type of school (up to 12/12)	2	83	SMD (Random, 95% CI)	‐0.53 [‐0.98, ‐0.08]
2.1 Primary school	0	0	SMD (Random, 95% CI)	0.0 [0.0, 0.0]
2.2 Secondary school	2	83	SMD (Random, 95% CI)	‐0.53 [‐0.98, ‐0.08]
3 Difference in school response to aggressive acts + other acts by school (post test)	5	265	SMD (Random, 95% CI)	‐0.30 [‐0.85, 0.25]
3.1 Primary school	1	48	SMD (Random, 95% CI)	0.5 [‐0.07, 1.07]
3.2 Secondary school	4	217	SMD (Random, 95% CI)	‐0.50 [‐1.09, 0.08]
4 Difference in school response to aggressive acts + other acts by school (up to 12 months)	2	83	SMD (Random, 95% CI)	0.03 [‐0.42, 0.47]
4.1 Primary school	0	0	SMD (Random, 95% CI)	0.0 [0.0, 0.0]
4.2 Secondary school	2	83	SMD (Random, 95% CI)	0.03 [‐0.42, 0.47]