Table 1.

Prevalence of TP antibody in the donors by gender, age, number of donations, and educational level.

Variable	Number of donors	Number of seropositives	Prevalence (%)	95% CI of prevalence (%)	p value
Total	992646	4316	0.43	0.420–0.446
Gender
Men	595933	2683	0.44	0.431–0.465	χ 2 = 8.191, p > 0.05
Women	396713	1633	0.41	0.390–0.430
Age
18–24 years	443701	637	0.14	0.132–0.155	χ 2 = 2207.796, p < 0.001
25–34 years	278209	1259	0.45	0.426–0.475
35–44 years	175293	1549	0.88	0.833–0.919
45–54 years	92534	859	0.93	0.859–0.981
55–60 years	2909	12	0.41	0.179–0.643
Number of donations
1	657886	3760	0.57	0.550–0.586	χ 2 = 842.45, p < 0.001
≥2	334760	556	0.17	0.152–0.180
Education level
Postgraduate	14912	17	0.11	0.060–0.168	χ 2 = 1964.844, p < 0.001
Bachelor	219580	246	0.11	0.098–0.126
College degree	214390	497	0.23	0.211–0.252
High school	153916	905	0.59	0.547–0.623
Junior high school	139814	1305	0.93	0.875–0.975
Primary education	9853	154	1.56	1.298–1.780
Not defined	240181	1192	0.50	0.466–0.522