Table 2 

Differences between groups NAC and placebo on scores at Week 8 (at randomization) in terms of symptoms and functioning. 

Characteristics 
Descriptive statistic 
Total sample n = 149 
NAC n = 76 
Placebo n = 7 3 
Test statistic 
Value 
df 
P 


Symptoms 

YMRS^{a} 
M(SD) 
1.5 (2.1) 
1.7 (2.4) 
1.4 (1.9) 
ttest 
0.37 
130 
.716 
MADRS^{b} 
M(SD) 
12.6 (9.8) 
13.1 (9.72) 
12.2 (9.9) 
ttest 
0.47 
130 
.638 
BDRS^{a} 
M(SD) 
10.7 (9.1) 
11.3 (8.5) 
10.1 (9.7) 
ttest 
1.20 
130 
.233 
CGIBP Severity 

Depression^{a } 
M(SD) 
2.8 (1.2) 
2.9 (1.2) 
2.8 (1.2) 
ttest 
0.49 
129 
.625 
Mania^{a} 
M(SD) 
1.3 (0.7) 
1.4 (0.7) 
1.3 (0.6) 
ttest 
0.17 
129 
.620 
Overall^{a} 
M(SD) 
2.9 (1.2) 
2.9 (1.2) 
2.8 (1.2) 
ttest 
0.29 
128 
.771 
CGIBP Improvement 

Depression^{a} 
M(SD) 
2.5 (1.2) 
2.5 (1.1) 
2.6 (1.3) 
ttest 
0.17 
129 
.864 
Mania^{a} 
M(SD) 
3.8 (0.7) 
3.8 (0.7) 
3.9 (0.7) 
ttest 
0.63 
130 
.533 
Overall^{a} 
M(SD) 
2.6 (1.2) 
2.6 (1.2) 
2.7 (1.3) 
ttest 
0.30 
129 
.767 
Functioning 

GAF 
M(SD) 
72.2 (13.7) 
71.1 (13.3) 
73.3 (14.1) 
ttest 
0.92 
129 
.360 
SOFAS 
M(SD) 
72.1 (13.6) 
71.5 (13.0) 
72.6 (14.1) 
ttest 
0.46 
129 
.649 
LIFERIFT 
M(SD) 
11.2 (3.8) 
11.5 (3.9) 
10.9 (3.8) 
ttest 
0.83 
130 
.410 
SLICELIFE 
M(SD) 
16.5 (5.2) 
16.6 (5.3) 
16.5 (5.0) 
ttest 
0.17 
130 
.866 
QLESQ 
M(SD) 
53.4 (10.8) 
52.5 (10.6) 
54.3 (11.0) 
ttest 
0.98 
130 
.325 


YMRS, Young Mania Rating Scale; MADRS, MontgomeryAsberg Depression Rating Scale; BDRS, Bipolar Depression Rating Scale; CGIBP Clinical Global Impressions  Bipolar Disorder; GAF, Global Assessment of Functioning; SOFAS, Social and Occupational Assessment Scale; QLESQ, Quality of Life Enjoyment and Satisfaction Questionnaire. ^{a}Inferential statistics based on logarthmic transformed data (plus constant) because of extreme positive skewness. Untransformed descriptive statistics are reported; ^{b}Inferential statistics based on square root transformed data (plus constant) because of positive skewness. Untransformed descriptive statistics are reported. 

Berk et al. BMC Medicine 2012 10:91 doi:10.1186/174170151091 