Table 3.

Logistic regression predicting TTIs positive status

Demographic factors	TTIs
	Bivariate analysis		Multivariable analysis
	OR (95% CI)	p-value	aOR (95% CI)	p-value
Age
>55 (Reference)	1	–	1	–
18–25	2.690 (0.724–10.000)	0.140	2.616 (0.705–9.713)	0.151
26–35	2.874 (1.982–4.167)	<0.001	2.799 (1.948–4.023)	<0.001
36–45	2.611 (1.879–3.627)	<0.001	2.562 (1.862–3.525)	<0.001
46–55	1.802 (1.351–2.404)	<0.001	1.813 (1.376–2.389)	<0.001
Gender
Female (Reference)	1	–	1	–
Male	0.994 (0.810–1.219)	0.951	1.041 (0.852–1.271)	0.697
Previous donation history
First-time donor (Reference)	1	–	1	–
Repeat donor	0.260 (0.203–0.334)	<0.001	0.261 (0.204–0.334)	<0.001
Ethnicity
Han (Reference)	1	–	1	–
Minority	1.480 (0.963–2.273)	0.074	1.489 (0.974–2.276)	0.066
Marital status
Unmarried (Reference)	1	–	1	–
Married	0.681 (0.533–0.870)	0.002	0.720 (0.573–0.904)	0.005
Occupation
Others (Reference)	1	–	1	–
Teacher/civil servant/medical worker	0.350 (0.179–0.684)	0.002	0.355 (0.181–0.694)	0.002
Farmer	1.176 (0.761–1.817)	0.465	1.191 (0.772–1.838)	0.430
Student	1.119 (0.769–1.628)	0.556	1.000 (0.695–1.438)	1.000
Worker	1.187 (0.908–1.552)	0.209	1.227 (0.940–1.601)	0.133
Company employee	1.208 (0.901–1.620)	0.206	1.256 (0.940–1.678)	0.123
Education
Secondary School or below (Reference)	1	–	1	–
Masters/Bachelor degree	0.643 (0.488–0.848)	0.002	0.602 (0.467–0.775)	<0.001
Associate degree	1.007 (0.776–1.307	0.957	0.992 (0.770–1.277)	0.947