Table 1.
Descriptive statistics of the sample used in this study.
| MDD (N = 482) | HC (N = 525) | Test statistic | P value | Cohen’s d | |
|---|---|---|---|---|---|
| Age, M ± SD | 37.12 ± 13.47 | 31.68 ± 11.87 | t(962.3) = −6.77a | <0.001 | 0.436 |
| Sex, f/m | 311/171 | 321/204 | χ²(1) = 1.23b | 0.268 | – |
| IQMVT, M ± SD | 113.79 ± 13.71 | 114.98 ± 13.72 | t(1005) = 1.38c | 0.170 | 0.087 |
| Education years, M ± SD | 13.15 ± 2.76 | 13.98 ± 2.42 | t(1005) = 5.05c | <0.001 | 0.329 |
| BDI Sum, M ± SD | 17.99 ± 11.19 | 2.50 ± 2.15 | t(505.68) = −29.68a | <0.001 | 2.640 |
| TMT-A, M ± SD | 26.16 ± 10.36 | 22.52 ± 8.40 | t(927.0) = −6.10a | <0.001 | 0.401 |
| TMT-B, M ± SD | 57.12 ± 24.30 | 46.89 ± 17.30 | t(861.5) = −7.64a | <0.001 | 0.521 |
| DSST, M ± SD | 55.97 ± 12.17 | 65.45 ± 11.05 | t(973.2) = 12.9a | <0.001 | 0.827 |
| RAVLT-S, M ± SD | 55.73 ± 9.87 | 60.15 ± 8.27 | t(941.7) = 7.68a | <0.001 | 0.501 |
| RAVLT-R, M ± SD | 13.14 ± 2.99 | 13.90 ± 1.89 | t(799.2) = 4.75a | <0.001 | 0.336 |
| CBTT-f, M ± SD | 8.65 ± 1.84 | 9.44 ± 1.96 | t(1005) = 6.63c | <0.001 | 0.418 |
| CBTT-b, M ± SD | 8.04 ± 1.91 | 9.00 ± 1.71 | t(969.0) = 8.42a | <0.001 | 0.541 |
| d2, M ± SD | 168.05 ± 43.05 | 194.00 ± 42.86 | t(1005) = 9.58c | <0.001 | 0.604 |
| LNS, M ± SD | 15.83 ± 3.20 | 16.96 ± 3.09 | t(1005) = 5.70c | <0.001 | 0.360 |
| VF-C, M ± SD | 23.20 ± 6.01 | 25.45 ± 5.63 | t(1005) = 6.15c | <0.001 | 0.388 |
| VF-P, M ± SD | 11.32 ± 4.22 | 12.44 ± 4.41 | t(1005) = 4.11c | <0.001 | 0.259 |
| VF-A, M ± SD | 15.27 ± 3.48 | 16.90 ± 3.26 | t(1005) = 7.62c | <0.001 | 0.481 |
| General Cognitive Performance factor, M ± SD | −0.37 ± 1.03 | 0.34 ± 0.84 | t(1005) = −12.04 | <0.001 | 0.935 |
| Number of hospitalizations, M ± SD | 1.66 ± 2.16 | – | – | – | – |
| Medication Load Index, M ± SD | 1.32 ± 1.43 | – | – | – | – |
| Comorbid diagnosis (yes/no) | 203/279 | – | – | – | – |
BDI Sum beck depression inventory, CBTT-f/b Corsi block-tapping test, forwards/backwards, d2 d2 test of attention, DSST digit symbol substitution test, HC healthy control, IQMVT Intelligence quotient evaluated with the multiple-choice vocabulary test version B (dt. “Mehrfachwahl-Wortschatz-Test Version B”), LNS letter–number–sequences test, M mean, MDD major depressive disorder, RAVLT-S/B Rey Auditory Verbal Learning Test, sum of all correct words/recognition, SD standard deviation, TMT-A/B trail making test, Version A/B, VF-C/P/A verbal fluency test, category/phonemic/alternating.
aTwo-sample t test assuming unequal variance, bPearson χ² test, ctwo-sample t test assuming equal variance.