Table 1.
Study population characteristics and neuropsychological function scores for the HELIX subcohort
| BiB | EDEN | INMA | KANC | MoBa | RHEA | Total | P | |
|---|---|---|---|---|---|---|---|---|
| (N = 166) | (N = 87) | (N = 314) | (N = 153) | (N = 249) | (N = 157) | (N = 1126) | ||
| Child sex | ||||||||
| Male | 91 (54.8%) | 50 (57.5%) | 164 (52.2%) | 84 (54.9%) | 131 (52.6%) | 88 (56.1%) | 608 (54.0%) | 0.9273a |
| Female | 75 (45.2%) | 37 (42.5%) | 150 (47.8%) | 69 (45.1%) | 118 (47.4%) | 69 (43.9%) | 518 (46.0%) | |
| Child age | ||||||||
| Years | 6.64 [6.15, 7.33] | 10.8 [9.28, 12.0] | 8.99 [7.56, 10.7] | 6.41 [5.44, 7.81] | 8.45 [6.92, 9.80] | 6.46 [6.02, 7.54] | 8.17 [5.44, 12.0] | < .0001b |
| Child ancestry | ||||||||
| European | 74 (44.6%) | 87 (100%) | 281 (89.5%) | 153 (100%) | 238 (95.6%) | 157 (100%) | 990 (87.9%) | < .0001a |
| Non-European | 92 (55.4%) | 0 (0%) | 33 (10.5%) | 0 (0%) | 11 (4.4%) | 0 (0%) | 136 (12.1%) | |
| SES | ||||||||
| Low | 47 (28.3%) | 0 (0%) | 30 (9.6%) | 20 (13.1%) | 3 (1.2%) | 27 (17.2%) | 127 (11.3%) | < .0001a |
| Medium | 73 (44.0%) | 18 (20.7%) | 115 (36.6%) | 84 (54.9%) | 69 (27.7%) | 76 (48.4%) | 435 (38.6%) | |
| High | 46 (27.7%) | 69 (79.3%) | 166 (52.9%) | 48 (31.4%) | 177 (71.1%) | 54 (34.4%) | 560 (49.7%) | |
| (Missing) | 0 (0%) | 0 (0%) | 3 (1.0%) | 1 (0.7%) | 0 (0%) | 0 (0%) | 4 (0.4%) | |
| Maternal age | ||||||||
| Years | 28.0 [16.0, 42.0] | 30.1 [20.2, 40.8] | 32.1 [18.2, 43.0] | 28.5 [19.2, 43.5] | 32.0 [24.0, 43.0] | 30.9 [17.0, 42.3] | 31.0 [16.0, 43.5] | < .0001b |
| Maternal education | ||||||||
| Low | 76 (45.8%) | 8 (9.2%) | 75 (23.9%) | 9 (5.9%) | 0 (0%) | 7 (4.5%) | 175 (15.5%) | < .0001a |
| Medium | 21 (12.7%) | 33 (37.9%) | 117 (37.3%) | 56 (36.6%) | 48 (19.3%) | 90 (57.3%) | 365 (32.4%) | |
| High | 51 (30.7%) | 44 (50.6%) | 97 (30.9%) | 85 (55.6%) | 191 (76.7%) | 58 (36.9%) | 526 (46.7%) | |
| (Missing) | 18 (10.8%) | 2 (2.3%) | 25 (8.0%) | 3 (2.0%) | 10 (4.0%) | 2 (1.3%) | 60 (5.3%) | |
| Conner’s | ||||||||
| ADHD Index | 98.2 [66.4, 134] | 99.5 [82.1, 135] | 104 [74.9, 136] | 107 [65.2, 130] | 91.8 [70.8, 132] | 104 [67.5, 136] | 101 [65.2, 136] | < .0001b |
| Hyperactivity | 97.8 [65.9, 134] | 102 [92.3, 127] | 101 [84.8, 134] | 107 [54.5, 135] | 89.3 [74.5, 122] | 102 [63.7, 130] | 98.7 [54.5, 135] | < .0001b |
| Inattention | 91.6 [79.4, 135] | 93.6 [82.4, 133] | 105 [80.7, 134] | 111 [78.7, 131] | 92.3 [80.1, 134] | 98.4 [79.4, 134] | 99.3 [78.7, 135] | < .0001b |
| (Missing) | 0 (0%) | 0 (0%) | 3 (1.0%) | 0 (0%) | 0 (0%) | 4 (2.5%) | 7 (0.6%) | |
| CBCL | ||||||||
| ADHD Problems | 102 [73.0, 126] | 101 [82.1, 136] | 105 [77.6, 135] | 107 [70.5, 130] | 90.2 [75.6, 129] | 102 [73.5, 134] | 101 [70.5, 136] | < .0001b |
| (Missing) | 0 (0%) | 0 (0%) | 2 (0.6%) | 1 (0.7%) | 0 (0%) | 2 (1.3%) | 5 (0.4%) | |
| ANT | ||||||||
| HRT-SE | 104 [66.1, 126] | 106 [79.7, 141] | 99.2 [64.5, 142] | 105 [68.7, 132] | 95.0 [63.6, 136] | 99.8 [61.5, 129] | 100 [61.5, 142] | < .0001b |
| Zeros | 96.6 [58.2, 143] | 106 [98.2, 139] | 100 [82.8, 128] | 91.5 [28.7, 148] | 99.6 [78.0, 141] | 97.5 [57.3, 147] | 100 [28.7, 148] | < .0001b |
| Omissions | 96.8 [59.6, 145] | 111 [102,126] | 102 [84.1, 145] | 103 [40.8, 167] | 96.4 [73.6, 132] | 91.3 [45.3, 150] | 100 [40.8, 167] | < .0001b |
| Conflict | 99.3 [51.0, 172] | 100 [45.1, 134] | 99.2 [58.8, 149] | 99.8 [27.0, 136] | 98.9 [69.8, 204] | 97.9 [-5.19, 172] | 99.3 [-5.19, 204] | 0.7730b |
| (Missing) | 3 (1.8%) | 6 (6.9%) | 3 (1.0%) | 0 (0%) | 0 (0%) | 0 (0%) | 12 (1.1%) | |
| N-back | ||||||||
| d’ | 98.3 [68.5, 147] | 95.9 [62.8, 131] | 101 [60.8, 142] | NA | 102 [63.6, 139] | 102 [68.4, 149] | 101 [60.8, 149] | 0.0864b |
| (Missing) | 26 (15.7%) | 7 (8.0%) | 8 (2.5%) | 153 (100%) | 10 (4.0%) | 15 (9.6%) | 219 (19.4%) | |
Presented are N (%) or median [min, max]. Measures of behavior and neuropsychological function are presented after transformation of raw data
BiB Born in Bradford (UK), EDEN Étude des Déterminants pré et postnatals du développement et de la santé de l’Enfant (France), INMA INfancia y Medio Ambiente (Spain), KANC Kaunas cohort (Lithuania), MoBa Norwegian Mother, Father and Child Cohort Study, RHEA Mother–Child Cohort study in Crete (Greece), SES Socioeconomic status, CBCL Child Behavior Checklist, ANT Attention Network Test, HRT-SE Hit reaction time standard error
P-values for significant difference between cohorts
ap-values from chi-square test of homogeneity
bp-values from one-way ANOVA