Table 5.

Independent sample t-test for parents’ satisfaction regarding knowledge acquired by children and parents knowledge of playing chess.

	t-test for equality of means
	Group	N	Mean	S. D.	t	df	p	Mean difference	Std. Error difference	CI4
	Do you know to play chess									Lower	Upper
Q11: To what extent are you satisfied with the amount of knowledge the child has acquired during chess training? 1 = to a very small extent; 5 = to a great extent	Yes	516	4.07	0.85	2.096	772	0.036	0.13	0.06	0.00	0.25
	No	258	3.93	0.79