Table 3.
The cognitive function scores after 4 weeks L-theanine or placebo administration.
| Cognitive functions | Pretreatmnent | Posttreatment | Wilcoxon Signed-Rank Test | Pretreatment | Postreatment | Wilcoxon Signed-Rank Test | Score Changes | Mann-Whitney U Test | |
|---|---|---|---|---|---|---|---|---|---|
| L-theanine | Placebo | L-theanine | Placebo | ||||||
| Trail Making Test A (sec) | 27.4 ± 9.78 | 25.9 ± 10.2 | W = 170.5, p = 0.31, r = −0.19 |
29.1 ± 10.7 | 25.9 ± 10.3 | W = 123.5, p = 0.042, r = −0.37 |
−1.57 ± 9.68 | −3.27 ± 7.48 | U = 410.0, p = 0.55, r = 0.08 |
| Trail Making Test B (sec) | 62.4 ± 22.0 | 59.6 ± 24.8 | W = 136.5, p = 0.13, r = −0.28 |
63.9 ± 22.9 | 58.6 ± 20.4 | W = 121.5, p = 0.038, r = −0.38 |
−2.83 ± 18.5 | −5.23 ± 14.9 | U = 428.0, p = 0.75, r = 0.04 |
| Stroop test response latency (msec) | 1176 ± 219 | 1159 ± 228 | W = 149.0, p = 0.50, r = −0.12 |
1188 ± 259 | 1140 ± 217 | W = 154.5, p = 0.27, r = −0.20 |
−16.7 ± 158 | −47.9 ± 183 | U = 422.5, p = 0.68, r = 0.05 |
| Stroop test error rate (%) | 1.04 ± 1.62 | 1.81 ± 2.37 | W = 130.0, p = 0.15, r = 0.26 |
0.83 ± 1.51 | 1.32 ± 2.35 | W = 74.0, p = 0.42, r = 0.15 |
0.76 ± 2.41 | 0.49 ± 2.10 | U = 426.0, p = 0.71, r = 0.05 |
| Brief Assessment of Cognition in Schizophrenia | |||||||||
| verbal memory | 52.2 ± 7.68 | 52.5 ± 7.74 | W = 183.0, p = 0.85, r = 0.04 |
52.7 ± 9.05 | 51.5 ± 9.69 | W = 182.0, p = 0.63, r = −0.09 |
0.30 ± 8.57 | −1.20 ± 9.53 | U = 414.5, p = 0.60, r = 0.07 |
| working memory | 20.9 ± 4.14 | 21.5 ± 4.43 | W = 194.5, p = 0.39, r = 0.16 |
21.5 ± 4.91 | 21.4 ± 4.83 | W = 158.5, p = 0.91, r = −0.02 |
0.57 ± 3.87 | −0.03 ± 3.31 | U = 397.0, p = 0.43, r = 0.10 |
| motor speed | 83.7 ± 12.6 | 84.0 ± 12.5 | W = 193.5, p = 0.65, r = 0.08 |
83.2 ± 13.0 | 83.6 ± 13.3 | W = 204.5, p = 0.71, r = 0.07 |
0.37 ± 7.80 | 0.43 ± 7.94 | U = 439.5, p = 0.88, r = −0.02 |
| verbal fluency | 50.3 ± 13.0 | 54.9 ± 10.4 | W = 364.5, p = 0.001, r = 0.58 |
52.3 ± 9.80 | 54.7 ± 12.2 | W = 299.5, p = 0.076, r = 0.33 |
4.57 ± 7.13 | 2.33 ± 7.26 | U = 336.5, p = 0.22, r = 0.20 |
| category fluency | 21.9 ± 5.87 | 23.1 ± 5.30 | W = 271.5, p = 0.12, r = 0.29 |
22.4 ± 4.48 | 23.3 ± 5.49 | W = 244.0, p = 0.35, r = 0.17 |
1.20 ± 4.23 | 0.90 ± 5.91 | U = 442.5, p = 0.91, r = 0.02 |
| letter fluency | 28.4 ± 8.43 | 31.7 ± 6.94 | W = 348.5, p = 0.001, r = 0.61 |
29.9 ± 7.28 | 31.4 ± 9.68 | W = 283.5, p = 0.29, r = 0.19 |
3.37 ± 4.63 | 1.43 ± 5.83 | U = 344.0, p = 0.12, r = 0.20 |
| attention | 64.4 ± 11.6 | 62.9 ± 11.7 | W = 139.0, p = 0.53, r = −0.12 |
62.6 ± 11.3 | 62.9 ± 10.1 | W = 204.0, p = 0.47, r = 0.13 |
−1.47 ± 7.37 | 0.33 ± 4.97 | U = 308.5, p = 0.30, r = −0.13 |
| executive function | 17.4 ± 2.71 | 18.5 ± 1.72 | W = 208.5, p = 0.031, r = 0.40 |
18.2 ± 1.77 | 18.5 ± 1.63 | W = 205.0, p = 0.24, r = 0.21 |
1.10 ± 2.52 | 0.33 ± 1.81 | U = 397.0, p = 0.43, r = 0.10 |
Values are represented as mean ± standard deviation. Significant p-values are shown in bold cases.