Table 1 Baseline characteristics of the study population investigating depressive disorder in the primary analysis
| Â | Before matching | After matching | ||||
|---|---|---|---|---|---|---|
Long-term users (n = 1400) | Short-term users (n = 2970) | Absolute SMD | Long-term users (n = 1309) | Short-term users (n = 2199) | Absolute SMD | |
 Age, mean (SD) | 8.6 \(\pm\) 2.4 | 8.8 \(\pm\) 2.6 | 0.08 | 8.6 \(\pm\) 2.4 | 8.6 \(\pm\) 2.4 | 0.01 |
 Gender, male | 1209 (86.4) | 2437 (82.1) | 0.13 | 1132 (85.8) | 1866 (84.8) | 0.01 |
Neuropsychiatric disease history, n (%) | ||||||
 Anxiety disorder | 118 (8.4) | 206 (6.9) | 0.14 | 99 (7.5) | 170 (7.7) | 0.05 |
 Bipolar disorder | 107 (7.6) | 134 (4.5) | 0.14 | 82 (6.2) | 116 (5.3) | 0.02 |
 Autism spectrum disorder | 109 (7.8) | 197 (6.6) | 0.14 | 89 (6.7) | 169 (7.7) | 0.02 |
 Sleep disorder | 17 (1.2) | 33 (1.1) | 0.03 | 16 (1.2) | 26 (1.2) | 0.01 |
 Tic disorder | 152 (10.9) | 182 (6.1) | 0.16 | 128 (9.7) | 167 (7.6) | 0.03 |
 Conduct disorder and ODD | 162 (11.6) | 262 (8.8) | 0.18 | 129 (9.8) | 224 (10.2) | 0.05 |
 Psychotic disorder | 59 (4.2) | 43 (1.4) | 0.12 | 55 (4.2) | 38 (1.7) | 0.05 |
 Daily methylphenidate dose, mean (SD) | 22.5 \(\pm\) 8.6 | 19.1 \(\pm\) 8.4 | 0.39 | 22.2 \(\pm\) 8.4 | 20.9 \(\pm\) 8.2 | 0.02 |