Table 1 Characteristics of the study population presented as count (sample size), median (5th-95th percentile: pregnancy duration, birth weight), or percentage (gender, season at birth, age at heel prick, laboratory)
From: Neonatal heel prick screening TSH concentration in the Netherlands as indicator of iodine status
N | total population | nTSH subpopulation | |||
|---|---|---|---|---|---|
1,435,600 | 264,407 | ||||
Gender (%) | male | 51 | χ2 = 1017, 1 d.f., p < 0.0001 | 59 | χ2 = 9074, 1 d.f., p < 0.0001 |
Season at birth (%) | spring | 24 | χ2 = 2850, 3 d.f., p < 0.0001 | 24 | χ2 = 826, 3 d.f., p < 0.0001 |
summer | 24 | 24 | |||
autumn | 27 | 27 | |||
winter | 25 | 25 | |||
Age at heel prick (%) | day 3 | 8 | χ2 = 1,007,684, 4 d.f., p < 0.0001 | 7 | χ2 = 148,329, 4 d.f., p < 0.0001 |
day 4 | 50 | 46 | |||
day 5 | 24 | 24 | |||
day 6 | 15 | 19 | |||
day 7 | 3 | 4 | |||
Laboratory (%) | Amsterdam | 20 | χ2 = 34,673, 4 d.f., p < 0.0001 | 20 | χ2 = 6307, 4 d.f., p < 0.0001 |
Bilthoven | 21 | 21 | |||
Capelle | 25 | 25 | |||
Tilburg | 17 | 17 | |||
Zwolle | 17 | 17 | |||
Pregnancy duration (days) | 280 (262-292) | 277 (260-291) | |||
Birth weight (kg) | 3.5 (2.8-4.3) | 3.4 (2.7-4.2) | |||