Table 1

Characteristics of conscripts, who were evaluated at the draft board and had a Boerge Prien test (BPP)
Otitis media hospitalisation in childhood
Variables Yes No Total
Men evaluated by the draft board, n (%) 1000 (5.4%) 17 412 (94.6%) 18 412 (100%)
BPP score, median (interquartile range) 42 (35–48) 44 (38–50) 44 (38–50)
Proportion with a BPP score in the bottom quartile (%) 312 (31.2%) 4370 (25.1%) 4682 (25.4%)
Birth weight in grams, median (interquartile range) 3450 (3125–3760) 3510 (3160–3875) 3500 (3150–3875)
Gestational age, no. (%)
Preterm (<37 weeks) 53 (5.3%) 648 (3.7%) 701 (3.8%)
Term (31–41 weeks) 708 (70.8%) 12 762 (73.3%) 13 470 (73.2%)
Post-term (≥42 weeks) 66 (6.6%) 1209 (6.9%) 1275 (6.9%)
Missing 2793 (16.0%) 173 (17.3%) 2966 (16.1%)
Small for gestational age, no. (%)
Yes 17 (1.7%) 141 (0.8%) 158 (0.9%)
No 808 (80.8%) 14 385 (82.6%) 15 193 (82.5%)
Missing 175 (17.5%) 2886 (16.6%) 3061 (16.6%)
Apgar score at 5 minutes after birth, no. (%)
<7 6 (0.6%) 99 (0.6%) 105 (0.6%)
≥7 908 (90.8%) 16 077 (92.3%) 16 985 (92.2%)
Missing 86 (8.6%) 1236 (7.1%) 1322 (7.2%)
Maternal age, n (%)
≤ 20 years 100 (10.0%) 1638 (9.4%) 1738 (9.4%)
21–35 years 852 (85.2%) 14 794 (84.9%) 15 646 (84.9%)
> 35 years 48 (4.8%) 980 (5.6%) 1028 (5.6%)
Mothers’ marital status at subject′s birth, n (%)
Married 595 (59.5%) 11 033 (63.4%) 11 628 (63.2%)
Unmarried 341 (34.1%) 5366 (30.8%) 5707 (31%)
Missing 64 (6.4%) 1013 (5.8%) 1077 (5.9%)
Birth order, n (%)
1 320 (32.0%) 6063 (34.8%) 6383 (34.7%)
2 368 (36.8%) 6148 (35.3%) 6516 (35.4%)
3 183 (18.3%) 3173 (18.2%) 3356 (18.2%)
4+ 129 (12.9%) 2026 (11.6%) 2155 (11.7%)
Missing 0 (0%) 2 (0.01%) 2 (0.01%)
Mode of delivery, no. (%)
Vaginal 796 (79.6%) 14 170 (81.4%) 14 966 (81.3%)
Caesarean 119 (11.9%) 1626 (9.3%) 1745 (9.5%)
Forceps or vacuum extraction 85 (8.5%) 1616 (9.3%) 1701 (9.2%)
Hearing score at conscription, no. (%)
Severe hearing impairment 78 (7.8%) 754 (4.3%) 832 (4.5%)
Moderate hearing impairment 274 (27.4) 3902 (22.4%) 4176 (22.7%)
No hearing impairment 641 (64.1%) 12 653 (72.7%) 13 294 (72.2%)
Missing 7 (0.7%) 103 (0.6%) 110 (0.6%)

Mortensen et al.

Mortensen et al. BMC Pediatrics 2013 13:8   doi:10.1186/1471-2431-13-8

Open Data