TABLE 1.

Sample characteristics.

	Gender				Type of school				IQ subtests
	F		M		Public		Private		Vocabulary		Matrix reasoning
	N	%	N	%	N	%	N	%	M	SD	M	SD
7 (n = 37)	19	16.38	18	15.78	24	20.68	13	11.40	11.44	2.59	10.56	2.19
8 (n = 41)	18	15.52	23	20.17	18	15.51	23	20.17	11.10	3.27	11.1	3.12
9 (n = 34)	18	15.38	16	14.03	17	14.66	17	14.91	11.59	2.53	10.74	3.26
10 (n = 46)	25	21,55	21	18.42	23	19.83	23	20.17	11.11	2.73	9.82	3.33
11 (n = 39)	20	17.24	19	16.66	19	16.38	20	17.54	11.73	3.27	9.91	3.09
12 (n = 33)	16	13.79	17	14.91	15	12.93	18	15.79	11.71	2.89	9.50	2.90
Total (n = 230)	116	100	114	100	116	100	114	100	11.42	2.88	10.26	3.04

The values in bold correspond to the significant values.