Table 1.
Baseline demographic, biological and behavioral characteristics for each group based on data from 432 randomized participants
| Characteristics | Participants | Network members | Overall | ||||
|---|---|---|---|---|---|---|---|
| Control (N = 92) |
Experimental (N = 99) |
Control (N = 114) |
Experimental (N = 127) |
Control (N = 206) |
Experimental (N = 226) |
Wald statistic z, p value | |
| Age (years) | 28 (25–33) | 29 (25–31) | 28 (25–33) | 28 (25–32) | 28 (25–33) | 29 (25–32) | z = 1.00, p = 0.32 |
| Age at first injection | 18 (16–21) | 18 (16–22) | 18 (16–21) | 19 (17–22) | 18 (16–21) | 18 (17–22) | z = −0.09, p = 0.92 |
| Sexually active (past 3 months) | 75 (82 %) | 85 (89 %) | 96 (86 %) | 104 (83 %) | 171 (84 %) | 189 (86 %) | z = 0.31, p = 0.76 |
| Number of sex partners (past 3 months) | 1 (1–1) | 1 (1–2) | 1 (1–2) | 1 (1–2) | 1 (1–2) | 1 (1–2) | z = −0.22, p = 0.83 |
| Using condoms (past 30 days) | z = −0.94, p = 0.35 | ||||||
| Never | 35 (55 %) | 32 (46 %) | 55 (68 %) | 45 (52 %) | 90 (62 %) | 77 (50 %) | |
| Sometimes | 11 (17 %) | 14 (20 %) | 15 (19 %) | 18(21 %) | 26 (18 %) | 32 (21 %) | |
| Always | 18 (28 %) | 23 (33 %) | 11 (14 %) | 23 (27 %) | 29 (20 %) | 46 (30 %) | |
| Number of roommates | 2 (1–3) | 3 (2–4) | 2 (1–3) | 3 (2–4) | 2 (1–3) | 3 (2–4) | z = −3.00, p = 0.003 |
| Male gender | 61 (66 %) | 68 (69 %) | 77 (68 %) | 78 (61 %) | 138 (67 %) | 146 (65 %) | z = −0.52, p = 0.60 |
| HIV-positive | 45 (49 %) | 41 (41 %) | 52 (47 %) | 49 (39 %) | 97 (48 %) | 90 (40 %) | z = −1.39, p = 0.16 |
| Educational level | z = 0.06, p = 0.95 | ||||||
| <Completed secondary | 9 (10 %) | 19 (19 %) | 15 (13 %) | 21 (17 %) | 24 (12 %) | 40 (18 %) | |
| Completed secondary | 33 (36 %) | 24 (24 %) | 43 (38 %) | 44 (35 %) | 76 (37 %) | 68 (30 %) | |
| Vocational or trade | 37 (40 %) | 45 (45 %) | 39 (35 %) | 51 (40 %) | 76 (37 %) | 96 (42 %) | |
| Some higher | 13 (14 %) | 11 (11 %) | 16 (14 %) | 11 (9 %) | 29 (14 %) | 22 (10 %) | |
| Source of income | |||||||
| Wages | 32 (35 %) | 34 (35 %) | 54 (48 %) | 61 (48 %) | 86 (42 %) | 95 (42 %) | z = 0.10, p = 0.92 |
| Social assistance | 15 (16 %) | 12 (13 %) | 14 (12 %) | 15 (12 %) | 29 (14 %) | 27 (12 %) | z = 0.59, p = 0.56 |
| No legal income | 42 (47 %) | 47 (48 %) | 50 (45 %) | 56 (45 %) | 92 (46 %) | 103 (46 %) | z = 0.13, p = 0.89 |
| Friends and family | 66 (73 %) | 72 (74 %) | 76 (68 %) | 92 (72 %) | 142 (70 %) | 164 (73 %) | z = 0.81, p = 0.42 |
| Occupation level | z = −0.30, p = 0.77 | ||||||
| Full-time | 10 (11 %) | 12 (12 %) | 25 (22 %) | 21 (17 %) | 35 (17 %) | 33 (15 %) | |
| Part-time | 19 (21 %) | 18 (18 %) | 21 (19 %) | 38 (30 %) | 40 (20 %) | 56 (25 %) | |
| Unemployed | 63 (68 %) | 69 (70 %) | 67 (59 %) | 68 (54 %) | 130 (63 %) | 137 (61 %) | |
| Married or cohabitation | 35 (38 %) | 44 (44 %) | 48 (42 %) | 50 (39 %) | 83 (40 %) | 94 (42 %) | z = −0.22, p = 0.82 |
| Live with parents | 49 (53 %) | 55 (57 %) | 57 (50 %) | 69 (55 %) | 106 (52 %) | 124 (56 %) | z = 0.70, p = 0.49 |
| Commercial sex (F) | 4 (14 %) | 7 (24 %) | 2 (6 %) | 5 (11 %) | 6 (10 %) | 12 (16 %) | z = −1.03, p = 0.30 |
| Ever been Homeless | 6 (7 %) | 7 (7 %) | 4 (4 %) | 10 (8 %) | 10 (5 %) | 17 (8 %) | z = 1.11, p = 0.27 |
| Ever been in prison | 5 (6 %) | 2 (2 %) | 5 (4 %) | 6 (5 %) | 10 (5 %) | 8 (4 %) | z = −0.72, p = 0.47 |
| Alcohol use (past 30 days) | z = −0.14, p = 0.89 | ||||||
| Less than every week | 3 (37 %) | 32 (32 %) | 42 (37 %) | 49 (39 %) | 75 (37 %) | 81 (36 %) | |
| Every week | 35 (39 %) | 39 (39 %) | 39 (35 %) | 46 (37 %) | 74 (37 %) | 85 (38 %) | |
| Almost every day | 21 (24 %) | 28 (28 %) | 32 (28 %) | 31 (25 %) | 53 (26 %) | 59 (26 %) | |
| Injecting any drugs (past 30 days) | 92 (100 %) | 99 (100 %) | 109 (96 %) | 117 (92 %) | 201 (98 %) | 216 (96 %) | z = −1.43, p = 0.15 |
| Heroin injecting | 90 (98 %) | 96 (98 %) | 101 (93 %) | 110 (94 %) | 191 (95 %) | 206 (96 %) | z = 0.37, p = 0.71 |
| Stimulants injecting | 26 (28 %) | 38 (38 %) | 33 (30 %) | 28 (24 %) | 59 (29 %) | 66 (31 %) | z = 0.23, p = 0.82 |
| Mixture | 8 (9 %) | 6 (6 %) | 7 (6 %) | 6 (5 %) | 15 (7 %) | 12 (6 %) | z = −0.79, p = 0.43 |
| Unsafe injection practicesa (3 months) | 75 (82 %) | 82 (83 %) | 79 (72 %) | 94 (80 %) | 154 (77 %) | 176 (81 %) | z = 1.16, p = 0.25 |
Values expressed as count (percentage) or median (IQR). p values computed based on Wald tests from linear, logistic, or Poisson regression GEE models with the characteristic (row variable) as the dependent variable and randomization arm (control or experimental) as the independent variable
a
Unsafe injection practices is a combined variable including any of the following: needle or syringe sharing, shared syringe water, common dish or common drug source