Table 1.

Features of the teenagers and the mothers by the mothers' HBI statuses^a

Feature	HBI mothers (n = 40)		Non-HBI mothers (n = 53)		P valueb
	No.	Prop (%)	No.	Prop (%)
Mothersc
Education: junior middle school or above	31	77.5	39	73.5	0.66
Occupation: peasant	22	55.0	28	52.8	0.50
Annual family income ≥ 50,000 yuan	26	65.0	32	60.4	0.65
ALT ≥ 40 U/liter	2	5.0	6	11.3	0.46*
anti-HBc positive	32	80.0	41	77.4	0.76
anti-HBs positive	8	20.0	30	56.6	<0.01
Teenagersd
Sex (male)	22	55.0	31	58.5	0.74
Vaginal delivery: yes	34	85.0	40	75.5	0.26
Full-term delivery: yes	40	100.0	51	96.2	0.50*
Only breastfeeding up to 6 months: yes	32	80.0	43	81.1	0.89
Normal infantile growth and development: yes	33	82.5	42	79.2	0.69
Passive smoking: yes	22	55.0	34	64.2	0.33
Dental treatment: yes	18	45.0	23	43.4	0.88
History of diseases: yes	4	10.0	2	3.8	0.40*
History of injury: yes	36	90.0	49	92.5	0.72*
Sharing of toothbrush: yes	3	7.5	1	1.9	0.31*
Transfusion history: yes	2	5.0	0	0.0	0.18*
History of surgical operation: yes	4	10.0	1	1.9	0.16*
Initial HBV vaccine response: yes	34	85.0	46	86.8	0.81
History of booster: yes	34	85.0	41	77.4	0.36
ALT ≥ 40 U/liter	1	2.5	4	7.5	0.46

^aHBI, hepatitis B virus infection; Prop, proportion; ALT, alanine aminotransferase; anti-HBs, antibody to hepatitis B virus surface antigen; anti-HBc, antibody to hepatitis B virus core antigen.

^b*, Fisher's exact test.

^cAge in years (mean ± standard deviation), 38.5 ± 2.4 (HBI mothers) or 39.9 ± 3.9 (non-HBI mothers) (P = 0.04).

^dAge in years (mean ± standard deviation), 13.7 ± 0.1 (HBI mothers) or 13.7 ± 0.1 (non-HBI mothers) (P = 0.72); birth weight in kilograms (mean ± standard deviation), 3.26 ± 0.40 (HBI mothers) or 3.35 ± 0.37 (non-HBI mothers) (P = 0.26).