Table 3. Seroconversion rates of influenza antibody after immunization in the study groups.

Age group	Subgroup	No. of subjects	Antibody seroconversion (H1N1)			Antibody seroconversion (H3N2)			Antibody seroconversion (B)
			No.	Percentage	P value	No.	Percentage	P value	No.	Percentage	P value
3–10 y	T1	149	128	85.9		140	94		136	91.3
	T2	146	123	83.7	<0.001*	140	95.2	<0.001*	132	89.8	<0.001*
	T3	140	126	90	0.285†	133	95	0.870†	129	92.1	0.779†
	C	218	36	16.4		31	14.2		80	36.5
11–17 y	T1	166	161	97		164	98.8		125	75.3
	T2	166	152	91.6	<0.001*	161	97	<0.001*	135	81.3	<0.001*
	T3	159	147	91.9	0.081†	157	98.1	0.499†	130	81.3	0.301†
	C	251	14	5.6		6	2.4		11	4.4
18–54 y	T1	155	139	89.1		115	73.7		95	60.9
	T2	156	136	87.2	<0.001*	121	77.6	<0.001*	95	60.9	<0.001*
	T3	151	134	88.7	0.854†	117	77.5	0.661†	101	66.9	0.458†
	C	229	35	15.2		14	6.1		46	20
≥55 y	T1	152	127	83		145	94.8		116	75.8
	T2	150	130	86.7	<0.001*	145	96.7	<0.001*	122	81.3	<0.001*
	T3	162	141	87	0.537†	156	96.3	0.675†	127	78.4	0.505†
	C	234	18	7.7		18	7.7		14	6

Seroconversion rate, the proportion of subjects whose antibody GMT met the definition of seroconversion after vaccination; H1N1, H3N2, B, three strains of influenza; *P value between experimental and control groups; ^†P value between three experimental groups (three batches of influenza vaccine).