Table 2.

Student’s t-test test for group A and B, for each testing.

Test	Test 1 Initial Test		Test 2 3 Weeks		Test 3 3 Months		Test 4 6 Months		Test 5 1 Year		Statistic Significance
	t	p	t	p	t	p	t	p	t	p
1	−5	<0.001	−1.91 *	0.325 *	2.32 ***	0.022 ***	3.11	0.002	3.36	0.001	Yes
2	−5.53	<0.001	−2.46 **	0.016 **	2.81	0.006	5.45	<0.001	7.08	<0.001	Yes

* indicates no significant differences between average values for two groups (|t_calculate| < t_table and p > 0.05). ** indicates significant differences between average values for two groups (|t_calculate| > t_table and p < 0.02). *** indicates significant differences between average values for two groups (|t_calculate| > t_table and p < 0.05), without * indicates significant differences between average values for two groups (|t_calculate| > t_table and p < 0.01), if t is negative, then the average for group B is more than average for group A, t_table = 2.575 significant level 1%; t_table = 2.326 significant level 2%; t_table = 1.959 significant level 5%.