Table 1 Covariates in relation to immigration status in controls and in relation to the risk of childhood autism
From: The risk of childhood autism among second-generation migrants in Finland: a case–control study
Immigration | Relationship between covariates and childhood autism p-valuea | |||||
|---|---|---|---|---|---|---|
Covariates | Both parents Finnish n (%) | Mother only immigrated n (%) | Father only immigrated n (%) | Both parents immigrated n (%) | p-valuea | |
Maternal age (≥median, 29 years) | 2 386 (55.9) | 48 (60.0) | 48 (62.3) | 34 (36.6) | 0.001 | <0.001 |
mean (years) | 29.5 | 30.3 | 30.1 | 27.4 | ||
SD (years) | 5.3 | 5.2 | 5.2 | 4.7 | ||
Paternal age (≥median, 32 years) | 2 055 (48.2) | 47 (58.8) | 41 (53.3) | 58 (62.4) | 0.01 | 0.003 |
mean (years) | 31.9 | 35.7 | 32.6 | 33.0 | ||
SD (years) | 5.9 | 7.7 | 6.7 | 5.8 | ||
Smokingb | 714 (17.2) | 10 (13.2) | 10 (13.2) | 1 (1.2) | <0.001 | 0.77 |
Previous births (≥2) | 1 105 (25.9) | 15 (18.8) | 18 (23.4) | 36 (38.7) | 0.02 | 0.22 |
Pre-term birth (<37 weeks) | 229 (5.4) | 8 (10.0) | 1 (1.3) | 7 (7.5) | 0.08 | 0.06 |
Low birthweight (<2500 g) | 135 (3.2) | 3 (3.8) | 0 (0) | 3 (3.2) | 0.45 | <0.001 |
mean (g) | 3598 | 3558 | 3580 | 3539 | ||
SD (g) | 546 | 450 | 490 | 529 | ||