Table 4.

Linear mixed model on the effect of the Breathing Break Intervention and time on children’s perceptions of a supportive classroom climate

	β	SE	df	t
Intercept	26.93	1.48	223	18.23	***
Posttest	−0.21	0.82	223	−3.05	**
Follow-up	0.03	0.81	223	0.55
Group (0 = ACG)	−0.04	1.53	7	−0.32
Sex (0 = male)	0.02	0.74	123	0.26
Parent education (0 = no vocational qualification)	0.07	0.92	123	1.05
Age	−0.11	0.01	223	−2.26	*
Group * posttest	0.19	1.05	223	2.56	*
Group * follow-up	−0.01	1.05	223	−0.17

***p < 0.001; **p < 0.01; *p < 0.05; ˙p < 0.10; ACG, active control group; n = 134