Table 2 Maternal and infant characteristics of responders via postal questionnaire vs. responders via telephone interview or online to 2-year neurodevelopmental follow-up
Characteristic | Postal completion | Telephone or online completion | RR [95% CI] for telephone/online | p |
|---|---|---|---|---|
Maternal characteristics | (n = 1183) | (n = 109) | ||
Age at birth of study child, mean (SD) | 30.6 (5.6) | 30.8 (5.2) | 1.01 [0.98 to 1.04] | 0.68 |
Non-white ethnic group, n (%) | 220 (18.6) | 30 (27.8) | 1.60 [1.08 to 2.38] | 0.02 |
Non-English first language, n (%) | 144 (12.4) | 21 (19.6) | 1.63 [1.04 to 2.56] | 0.03 |
Unsupported mother, n (%) | 119 (10.1) | 8 (7.3) | 0.73 [0.36 to 1.46] | 0.37 |
Highest educational qualification, n (%) | ||||
None or secondary education | 385 (33.1) | 30 (27.5) | Baseline | - |
Tertiary education | 690 (59.2) | 70 (64.2) | 1.27 [0.84 to 1.92] | 0.25 |
Other | 90 (7.7) | 9 (8.3) | 1.26 [0.62 to 2.56] | 0.53 |
Occupational status, n (%)a | ||||
Managerial, professional or intermediate | 689 (58.6) | 53 (50.0) | Baseline | - |
Semi-routine or routine | 164 (14.0) | 20 (18.9) | 1.52 [0.93 to 2.48] | 0.09 |
No occupation | 322 (27.4) | 33 (31.1) | 1.30 [0.86 to 1.97] | 0.21 |
Difficult financial situation, n (%) | 71 (6.0) | 9 (8.3) | 1.35 [0.71 to 2.58] | 0.36 |
Poor mental health, n (%) | 123 (10.4) | 18 (16.7) | 1.63 [1.01 to 2.61] | 0.05 |
Poor general health, n (%) | 73 (6.2) | 10 (9.2) | 1.47 [0.80 to 2.71] | 0.22 |
Infant characteristics | (n = 1296) | (n = 126) | ||
Late/moderately preterm, n (%)b | 607 (46.8) | 44 (34.9) | 0.64 [0.45, 0.90] | 0.01 |
Birthweight, n (%) | ||||
Low birthweight (1501-2500 g) | 372 (28.7) | 32 (25.4) | 0.86 [0.59 to 1.27] | 0.45 |
Very low birthweight (≤1500 g) | 16 (1.2) | 2 (1.6) | 1.21 [0.32 to 4.53] | 0.78 |
Fetal growth restriction, n (%)c | 242 (18.7) | 31 (24.6) | 1.37 [0.94 to 2.02] | 0.11 |
Multiple birth, n (%) | 229 (17.7) | 33 (26.2) | 1.57 [1.08 to 2.28] | 0.02 |
Any respiratory support, n (%)d | 95 (7.3) | 5 (4.0) | 0.55 [0.23 to 1.31] | 0.17 |
Intra-cranial abnormality, n (%)e | 11 (0.9) | 1 (0.8) | 0.94 [0.14 to 6.18] | 0.95 |
Major congenital anomaly, n (%) | 16 (1.2) | 0 (0.0) | - | - |
Any breast milk at discharge, n (%)f | 916 (70.7) | 85 (67.5) | 0.87 [0.61 to 1.24] | 0.45 |