Table 1 Maternal and children’s characteristics stratified by maternal ACE groups
| Â | Â | Number of ACEs | p-value for difference | p-value for trend | ||||
|---|---|---|---|---|---|---|---|---|
|  |  | 0 | 1 | 2 | 3 | ≥4 | ||
 N (%) | 602 (14.2) | 1919 (45.2) | 774 (18.2) | 369 (8.7) | 579 (13.7) |  |  | |
Maternal characteristics | Â | Â | Â | Â | Â | Â | Â | |
Age (years), mean (SD) | 33.7 (4.6) | 33.0 (4.5) | 32.9 (4.6) | 33.2 (4.8) | 33.3 (4.6) | 0.022 | 0.298 | |
Current marital status, n (%) |  |  |  |  |  | 0.012 | < 0.001 | |
| Â | Married | 588 (97.7) | 1855 (96.7) | 750 (96.9) | 351 (95.1) | 546 (94.3) | Â | Â |
| Â | Unmarrieda | 14 (2.3) | 64 (3.3) | 24 (3.1) | 18 (4.9) | 33 (5.7) | Â | Â |
Educational level, n (%) |  |  |  |  |  | < 0.001 | 0.840 | |
| Â | Junior high school or below | 23 (3.8) | 205 (10.7) | 80 (10.3) | 36 (9.8) | 43 (7.4) | Â | Â |
| Â | Senior high school | 108 (17.9) | 485 (25.3) | 197 (25.5) | 89 (24.2) | 109 (18.8) | Â | Â |
|  | Bachelor’s degree or above | 471 (78.2) | 1226 (64.0) | 497 (64.2) | 243 (66.0) | 427 (73.7) |  |  |
Monthly per-capita income, n (%) |  |  |  |  |  | < 0.001 | 0.725 | |
|  | ≤5000 RMBb | 135 (22.4) | 569 (29.7) | 209 (27.0) | 114 (30.9) | 148 (25.6) |  |  |
|  | 5001 ~ 10,000 RMB | 170 (28.2) | 492 (25.6) | 200 (25.8) | 90 (24.4) | 154 (26.6) |  |  |
|  | ≥10,001 RMB | 240 (39.9) | 587 (30.6) | 261 (33.7) | 127 (34.4) | 214 (37.0) |  |  |
| Â | Uncertain | 57 (9.5) | 271 (14.1) | 104 (13.4) | 38 (10.3) | 63 (10.9) | Â | Â |
Negative emotional states, n (%) | Â | Â | Â | Â | Â | Â | Â | |
|  | Depression | 3 (0.5) | 59 (3.1) | 35 (4.5) | 33 (8.9) | 88 (15.2) | < 0.001 | < 0.001 |
|  | Anxiety | 7 (1.2) | 91 (4.7) | 44 (5.7) | 45 (12.2) | 107 (18.5) | < 0.001 | < 0.001 |
|  | Stress | 6 (1.0) | 64 (3.3) | 39 (5.0) | 41 (11.1) | 94 (16.2) | < 0.001 | < 0.001 |
Parenting styles, mean (SD) | Â | Â | Â | Â | Â | Â | Â | |
|  | Emotional warmth | 24.6 (3.3) | 22.2 (4.8) | 22.4 (4.5) | 22.7 (4.1) | 23.1 (3.9) | < 0.001 | < 0.001 |
|  | Rejection | 7.0 (1.2) | 7.5 (1.7) | 7.7 (1.7) | 7.9 (1.8) | 8.1 (1.9) | < 0.001 | < 0.001 |
| Â | Overprotection | 15.5 (2.9) | 15.5 (2.9) | 15.7 (2.9) | 15.8 (2.7) | 15.9 (2.7) | 0.027 | 0.004 |
Children’s characteristics |  |  |  |  |  |  |  | |
Age (years), mean (SD) | 4.7 (1.0) | 4.6 (1.0) | 4.6 (1.0) | 4.6 (1.0) | 4.6 (1.0) | 0.308 | 0.345 | |
Gender, n (%) | Â | Â | Â | Â | Â | 0.498 | 0.133 | |
| Â | Boys | 320 (53.2) | 1012 (52.7) | 385 (49.7) | 185 (50.1) | 291 (50.3) | Â | Â |
| Â | Girls | 282 (46.8) | 907 (47.3) | 389 (50.3) | 184 (49.9) | 288 (49.7) | Â | Â |
Single-child status, n (%) |  |  |  |  |  | 0.001 | < 0.001 | |
| Â | No | 330 (54.8) | 1082 (56.4) | 419 (54.1) | 181 (49.1) | 274 (47.3) | Â | Â |
| Â | Yes | 272 (45.2) | 837 (43.6) | 355 (45.9) | 188 (50.9) | 305 (52.7) | Â | Â |
Primary caregivers, n (%) | Â | Â | Â | Â | Â | 0.130 | 0.004 | |
| Â | Mother | 470 (78.1) | 1426 (74.3) | 571 (73.8) | 255 (69.1) | 415 (71.7) | Â | Â |
| Â | Father | 18 (3.0) | 69 (3.6) | 23 (3.0) | 16 (4.3) | 21 (3.6) | Â | Â |
| Â | Others | 114 (18.9) | 424 (22.1) | 180 (23.3) | 98 (26.6) | 143 (24.7) | Â | Â |
Conduct problems, n (%) |  |  |  |  |  | < 0.001 | < 0.001 | |
| Â | No symptoms | 589 (97.8) | 1813 (94.5) | 717 (92.6) | 323 (87.5) | 486 (83.9) | Â | Â |
| Â | Symptoms of problematic behaviors | 13 (2.2) | 106 (5.5) | 57 (7.4) | 46 (12.5) | 93 (16.1) | Â | Â |
Learning problems, n (%) |  |  |  |  |  | < 0.001 | < 0.001 | |
| Â | No symptoms | 585 (97.2) | 1831 (95.4) | 715 (92.4) | 328 (88.9) | 494 (85.3) | Â | Â |
| Â | Symptoms of problematic behaviors | 17 (2.8) | 88 (4.6) | 59 (7.6) | 41 (11.1) | 85 (14.7) | Â | Â |
Psychosomatic problems, n (%) |  |  |  |  |  | < 0.001 | < 0.001 | |
| Â | No symptoms | 583 (96.8) | 1815 (94.6) | 701 (90.6) | 330 (89.4) | 503 (86.9) | Â | Â |
| Â | Symptoms of problematic behaviors | 19 (3.2) | 104 (5.4) | 73 (9.4) | 39 (10.6) | 76 (13.1) | Â | Â |
Impulsive-hyperactive, n (%) |  |  |  |  |  | < 0.001 | < 0.001 | |
| Â | No symptoms | 584 (97.0) | 1831 (95.4) | 724 (93.5) | 328 (88.9) | 491 (84.8) | Â | Â |
| Â | Symptoms of problematic behaviors | 18 (3.0) | 88 (4.6) | 50 (6.5) | 41 (11.1) | 88 (15.2) | Â | Â |
Anxiety, n (%) |  |  |  |  |  | < 0.001 | < 0.001 | |
| Â | No symptoms | 591 (98.2) | 1835 (95.6) | 731 (94.4) | 328 (88.9) | 512 (88.4) | Â | Â |
| Â | Symptoms of problematic behaviors | 11 (1.8) | 84 (4.4) | 43 (5.6) | 41 (11.1) | 67 (11.6) | Â | Â |
Hyperactivity index, n (%) |  |  |  |  |  | < 0.001 | < 0.001 | |
| Â | No symptoms | 580 (96.3) | 1806 (94.1) | 709 (91.6) | 318 (86.2) | 473 (81.7) | Â | Â |
| Â | Symptoms of problematic behaviors | 22 (3.7) | 113 (5.9) | 65 (8.4) | 51 (13.8) | 106 (18.3) | Â | Â |