Table 2.
Demographic characteristics by timing of ADHD medication initiation in newly diagnosed patients 2016–2023, N = 42,316
| Before diagnosis (n = 3,567) |
0–3 months after (n = 15,226) |
4–12 months after (n = 14,154) |
No initiation within 12 months (n = 9,369) | |
|---|---|---|---|---|
| Age; mean (SD) | 11.1 (3.3) | 11.0 (3.4) | 10.5 (3.3) | 10.2 (3.5) |
| Sex; n (%) | ||||
| Male | 2,208 (61.9) | 9,281 (61.0) | 8,812 (62.3) | 6,034 (64.4) |
| Female | 1,359 (38.1) | 5,945 (39.0) | 5,342 (37.7) | 3,335 (35.6) |
| Age category; n (%) | ||||
| 3–5 years | 75 (2.1) | 297 (2.0) | 510 (3.6) | 766 (8.2) |
| 6–9 years | 1,261 (35.4) | 5,827 (38.3) | 5,858 (41.4) | 3,709 (39.6) |
| 10–13 years | 1,210 (33.9) | 4,785 (31.4) | 4,661 (32.9) | 2,993 (31.9) |
| 14–17 years | 1,021 (28.6) | 4,317 (28.4) | 3,125 (22.1) | 1,901 (20.3) |
| Immigration status; n (%) | ||||
| Norwegian | 3,479 (97.5) | 14,901 (97.9) | 13,819 (97.6) | 9,003 (96.1) |
| Immigrants | 88 (2.5) | 325 (2.1) | 335 (2.4) | 366 (3.9) |
| Birth order; n (%) | ||||
| First | 1,712 (48.0) | 7,025 (46.1) | 6,732 (47.6) | 4,467 (47.7) |
| Second | 1,234 (34.6) | 5,350 (35.1) | 4,902 (34.6) | 3,154 (33.7) |
| Third | 454 (12.7) | 2,107 (13.8) | 1,900 (13.4) | 1,263 (13.5) |
| Fourth or higher | 156 (4.4) | 727 (4.8) | 601 (4.2) | 467 (5.0) |
| Missing | 11 (0.3) | 17 (0.1) | 19 (0.1) | 18 (0.2) |
| First medication; n (%) | ||||
| Methylphenidate | 3,344 (93.7) | 14,629 (96.1) | 13,728 (97.0) | - |
| Atomoxetine | 85 (2.4) | 278 (1.8) | 225 (1.5) | - |
| Lisdexamphetamine | 131 (3.7) | 301 (2.0) | 182 (1.2) | - |
| Guanfacine | < 5 | < 10 | 12 (0.1) | - |
| Amphetamine | < 5 | < 5 | < 5 | - |
| Dexamphetamine | < 5 | 10 (0.1) | < 10 | - |
| Child’s region of birth; n (%) | ||||
| Norway | 3,382 (94.8) | 14,546 (95.5) | 13,532 (95.6) | 8,803 (94.0) |
| Africa | 20 (0.6) | 57 (0.4) | 60 (0.4) | 58 (0.6) |
| Europe | 94 (2.6) | 328 (2.2) | 331 (2.3) | 281 (3.0) |
| Asia | 42 (1.2) | 177 (1.2) | 130 (0.9) | 151 (1.6) |
| America and Oceania | 29 (0.8) | 118 (0.8) | 100 (0.7) | 74 (0.8) |
| Missing | 0 (0.0) | 0 (0.0) | 1 (0.0) | 2 (0.0) |
| Child’s living situation; n (%) | ||||
| Two parents (married or cohabiting) | 2,059 (57.7) | 8,865 (58.2) | 8,302 (58.7) | 5,399 (57.6) |
| Others | 1,334 (37.4) | 5,784 (38.0) | 5,364 (37.9) | 3,670 (39.2) |
| Missing | 174 (4.9) | 577 (3.8) | 488 (3.4) | 300 (3.2) |
| Parental characteristics | ||||
| Mother’s education; n (%) | ||||
| ≤ 10 years | 705 (19.8) | 3,128 (20.5) | 2,949 (20.8) | 2,149 (22.9) |
| 11–13 years | 1,152 (32.3) | 5,121 (33.6) | 4,801 (33.9) | 3,011 (32.1) |
| ≥ 14 years | 1,670 (46.8) | 6,833 (44.9) | 6,262 (44.2) | 4,059 (43.3) |
| Missing | 40 (1.1) | 144 (0.9) | 142 (1.0) | 150 (1.6) |
| Father’s education; n (%) | ||||
| ≤ 10 years | 868 (24.3) | 3,670 (24.1) | 3,407 (24.1) | 2,230 (23.8) |
| 11–13 years | 1,532 (42.9) | 7,003 (46.0) | 6,668 (47.1) | 4,126 (44.0) |
| ≥ 14 years | 1,011 (28.3) | 4,016 (26.4) | 3,575 (25.3) | 2,506 (26.7) |
| Missing | 156 (4.4) | 537 (3.5) | 504 (3.6) | 507 (5.4) |
| Mother’s region of birth; n (%) | ||||
| Norway | 3,104 (87.0) | 13,476 (88.5) | 12,490 (88.2) | 7,552 (80.6) |
| Africa | 57 (1.6) | 176 (1.2) | 206 (1.5) | 306 (3.3) |
| Europe | 234 (6.6) | 871 (5.7) | 847 (6.0) | 805 (8.6) |
| Asia | 103 (2.9) | 451 (3.0) | 394 (2.8) | 486 (5.2) |
| America and Oceania | 57 (1.6) | 223 (1.5) | 191 (1.3) | 197 (2.1) |
| Missing | 12 (0.3) | 29 (0.2) | 26 (0.2) | 23 (0.2) |
| Father’s region of birth; n (%) | ||||
| Norway | 3,007 (84.3) | 13,080 (85.9) | 12,188 (86.1) | 7,342 (78.4) |
| Africa | 74 (2.1) | 202 (1.3) | 233 (1.6) | 321 (3.4) |
| Europe | 223 (6.3) | 906 (6.0) | 887 (6.3) | 783 (8.4) |
| Asia | 92 (2.6) | 407 (2.7) | 303 (2.1) | 422 (4.5) |
| America and Oceania | 61 (1.7) | 241 (1.6) | 200 (1.4) | 167 (1.8) |
| Missing | 110 (3.1) | 390 (2.6) | 343 (2.4) | 334 (3.6) |