Table 1 Demographics and group variables

Age mean (st dev)

9.92 (2.97)

10.10 (2.83)

10.02 (2.88)

U(87) = 906, p = 0.75, d = −0.04

Age min, max

4.60, 18.00

5.20, 17.20

4.60, 18.00

Gender ratio (f/m)

22/20

28/17

50/37

Chi2 = 0.86, p = 0.35

Socioeconomic status

3.04 (0.51)⁽¹⁾

3.07 (0.65)⁽²⁾

3.05 (0.58)⁽³⁾

U(87) = 850, p = 0.78, d = −0.04

Pedagogy interest

2.76 (0.44)⁽⁴⁾

2.51 (0.70)⁽⁵⁾

2.64 (0.59)⁽⁶⁾

U(87) = 744, p = 0.13, d = 0.16

Fluid intelligence

32.67 (4.14)

32.77 (3.26)⁽⁷⁾

32.53 (3.99)⁽⁸⁾

U(87) = 837, p = 0.45, d = −0.09