Table 1.

Characteristics of the study population.

Characteristic	No booster		Booster		Total
	N	%	N	%	N	%
Birth year
2012–2013	3567	97.43	94	2.57	3661	100.00
2010–2011	4195	96.50	152	3.50	4347	100.00
2008–2009	1429	92.13	122	7.87	1551	100.00
2006–2007	1126	87.97	154	12.03	1280	100.00
2004–2005	447	85.14	78	14.86	525	100.00
2002–2003	637	81.77	142	18.23	779	100.00
HBsAg of mother
Negative	7151	93.3	512	6.7	7663	100.00
Positive	279	89.1	34	10.9	313	100.00
Unknown	3971	95.3	196	4.7	4167	100.00
Total	11,401	93.9	742	6.1	12,143	100.00