Table 3 Intervention effects on pupils’ questionnaire data, stratified for school

Sitting time at school^a (min/day)

Primary school

I: 292.9(17.3)

C: 308.4(17.3)

I: 243.2(17.1)

C: 294.2(17.2)

I: 315.1(17.1)

C: 303.5(17.1)

Mid: − 0.070(0.050)

Post: 0.070(0.051)

Secondary school

I: 375.8 (11.4)

C: 362.2(12.5)

I: 366.5(11.4)

C: 314.7(12.5)

I: 372.3(11.4)

C: 357.6(12.5)

Mid: 0.058(0.028)

Post: − 0.014(0.028)

Relationship with classmates^a (1–5)

Primary school

I: 4.4(0.1)

C: 4.3(0.1)

I: 4.4(0.1)

C: 4.3(0.1)

I: 4.4(0.1)

C: 4.3(0.1)

Mid: 0.003(0.014)

Post: − 0.004(0.014)

Secondary school

I: 4.4(0.2)

C: 4.0(0.2)

I: 4.4(0.2)

C: 4.1(0.2)

I: 4.2(0.2)

C: 4.1(0.2)

Mid: −0.020(0.017)

Post: − 0.045(0.017)

Habit of breaking up sitting time (1–5)

Primary school

I: 3.5(0.2)

C: 3.6(0.2)

I: 3.7(0.2)

C: 3.5(0.2)

I: 3.7(0.2)

C: 3.4(0.2)

Mid: 0.338(0.244)

Post: 0.467(0.244)

Secondary school

I: 3.7(0.1)

C: 3.6(0.2)

I: 3.5(0.1)

C: 3.9(0.1)

I: 3.5(0.1)

C: 3.5(0.2)

Mid: −0.456(0.249)

Post: − 0.216(0.248)

Self-efficacy to break up sitting time ^a (1–5)

Primary school

I: 3.2(0.2)

C: 3.7(0.2)

I: 3.4(0.2)

C: 3.2(0.2)

I: 3.6(0.2)

C: 3.6(0.2)

Mid: 0.188(0.095)

Post: 0.130(0.096)

Secondary school

I: 3.0(0.1)

C: 3.1(0.2)

I: 2.9(0.1)

C: 3.1(0.2)

I: 3.0(0.1)

C: 3.4(0.2)

Mid: 0.026(0.086)

Post: −0.103(0.086)