Table 1.

Characteristics of Faroese Birth Cohort Members (N = 587) Examined During 7 Years of Follow-up

Variable	Result
Birth and infancy (n = 587)
Maternal smoking during pregnancy, No. (%)	171 (29.1)
Girls, No. (%)	278 (47.4)
Birth weight, mean (SD), g	3725.5 (505.9)
Birth weight ≤2500 g, No. (%)	5 (0.9)
Total duration of breastfeeding, mean (SD), mo	9.8 (6.7)
Prebooster examination (n = 532)
Age, mean (SD), y	5.0 (0.1)
Antibody concentration, median (IQR), IU/mL
Tetanus	0.22 (0.10-0.51)
Diphtheria	0.12 (0.05-0.40)
Postbooster examination (n = 456)
Age, mean (SD), y	5.2 (0.1)
Antibody concentration, median (IQR), IU/mL
Tetanus	35 (16-96)
Diphtheria	13 (6.4-26)
Age 7 years examination (n = 464)
Age, mean (SD), y	7.5 (0.1)
Antibody concentration, median (IQR), IU/mL
Tetanus	1.59 (0.65-4.60)
Diphtheria	0.68 (0.40-1.60)

Abbreviation: IQR, interquartile range.