Table 1.

Comparison of patient characteristics between fracture and control groups.

	Fracture group (M, 95% CI)	Control group (M, 95% CI)	p-value*
Cases (n)	325	318
Age (year)	5.1 (4.83–5.33)	5.0 (4.67–5.33)	0.0793
Sex (male/female)	200/125	216/102	0.0905a
BMI (kg/m2)	16.15 (15.70–16.42)	15.85 (15.60–16.00)	0.0522
Type of fracture (%)	Upper limb fractures (86.2)	N
	Lower limb fractures (13.8)	N
Non-fracture diseases (%)	N	Tenosynovitis (21.7)
	N	Muscular torticollis (28.6)
	N	Skin lacerations (11.6)
	N	others (34.9)
VC (µg/ml)	4.48 (3.93–4.97)	8.38 (7.83–9.24)	<0.0001

N, none; n, number; M, median; m, month; CI, confidence interval.

^*Mann–Whitney U-test.

^a Chi-square test.