Table 6. Univariate analysis after limiting the age from 6 months to 2 years.

		n	Treatment failure	rate	RR	95%CI
β-propiolactonation	Yes	488	46	9.43%	1.47	1.08	∼	2.01
	No	2574	165	6.41%
Acidification	Yes	1498	93	6.21%	0.82	0.63	∼	1.07
	No	1564	118	7.54%
Containing IgA	Yes	1986	139	7.00%	1.05	0.79	∼	1.38
	No	1076	72	6.69%

CI: confidence interval, RR: relative risk.