Table 1. Selected demographic and sexual behavior characteristics of 577 eligible HIV negative participants by willingness to participate at screening in a HIV-incidence cohort study (RV363 study).

	Willingness to Participate (N = 577)
	No	Yes	Do not Know
Age (categorized), n (%)
18–20	14 (2)	225 (39)	2 (0)
21–24	14 (2)	191 (33)	5 (1)
25–35	10 (2)	113 (20)	3 (1)
Gender
Male	23 (4)	272 (47)	7 (1)
Female	15 (3)	257 (45)	3 (1)
Highest level of Education attained, n (%)
≤ Primary school completed	3 (1)	54 (9)	0 (0)
Secondary school not completed	23 (4)	306 (53)	2 (0)
≥ Secondary school completed	12 (2)	169 (30)	8 (1)
Marital Status, n (%)
Single	32 (6)	434 (75)	9 (2)
Cohabiting or married	5 (1)	77 (13)	1 (0)
Separated or divorced	1 (0)	17 (3)	0 (0)
Monthly income in metical’s, n (%)
≤ 5000	32 (6)	459 (79)	10 (2)
>5000	6 (1)	70 (12)	0 (0)
Main occupation, n (%)
Student	22 (4)	292 (50)	7 (1)
Occasional Work	4 (1)	26 (5)	0 (0)
Permanent work	10 (2)	146 (25)	0 (0)
N/A a)	68 (12)
Ever received blood transfusion, n (%)
No	35 (6)	506 (88)	9 (2)
Yes	1 (0)	20 (3)	1 (0)
N/A a)	5(1)
Desire to get pregnant in the next year (n = 275 females only), n (%)
No	8 (3)	227 (83)	2 (1)
Yes	4 (1)	30 (11)	2 (1)
N/A a)	2 (1)
Age (years) of first sexual intercourse, n (%)
< 15 years old	10 (2)	81 (14)	1 (0)
15–18 years old	20 (3)	368 (64)	5 (1)
≥ 18 years	6 (1)	49 (8)	3 (0)
N/A a)	34 (6)
Perceived risk for HIV infection, n (%)b)
No risk	3 (0)	25 (4)	0 (0)
Some risk	32 (6)	459 (80)	9 (2)
High risk	0	38 (7)	1 (0)
N/A a)	10 (2)

^a) N/A—data not available. Only shown for variables ≥ 1% of data missing.

^b) Question phrased as “How would you classify your risk for getting infected with HIV”.