(b).

Symptom score change	BrainPower group		Placebo group		Total
	N	%	N	%	N	%
−3	2	4.3	1	2.0	3	3.1
−2	12	25.5	10	19.6	22	22.4
−1	20	42.6	12	23.5	32	32.7
0	12	25.5	15	29.4	27	27.6
+1	1	2.1	10	19.6	11	11.2
+2	0	0.0	2	3.9	2	2.0
+3	0	0.0	1	2.0	1	1.0
Total	47	100.0	51.0	100.0	98	100.0