Table 1. Demographic and risk behavior characteristics of the IDUs in five study sites.
| Variable | Total No.(%) N = 2080 | Zhaotong No.(%) N1 = 570 | Qujing No.(%) N2 = 229 | Kaiyuan No.(%) N3 = 329 | Baoshan No.(%) N4 = 472 | Yingjiang No.(%) N5 = 480 | chi-square test p 1 |
| Age | <0.001a | ||||||
| N(respondents) | 2071 | 569 | 225 | 329 | 472 | 476 | |
| mean(95%CI) | 31.7 (31.4,32.0) | 28.9 (28.4,29.4) | 29.2 (28.3,30.1) | 37.1 (36.4,37.8) | 32.0 (31.4,32.7) | 32.1(31.3,32.9) | |
| Gender | <0.001 | ||||||
| Male | 1937 (93.3) | 558 (97.9) | 228 (100) | 242 (73.6) | 433 (92.1) | 476 (99.2) | |
| Female | 140 (6.7) | 12 (2.1) | 0 (0) | 87 (26.4) | 37 (7.9) | 4 (0.8) | |
| Ethnicity | <0.001 | ||||||
| Han | 1557 (75.0) | 435 (76.3) | 217 (94.8) | 263 (79.9) | 440 (93.4) | 202 (42.3) | |
| Hui | 164 (7.9) | 115 (20.2) | 6 (2.6) | 32 (9.7) | 11 (2.3) | 0 (0) | |
| Dai | 206 (9.9) | 0 (0) | 0 (0) | 0 (0) | 7 (1.5) | 199 (41.7) | |
| Jingpo | 64 (3.1) | 0 (0) | 0 (0) | 0 (0) | 3 (0.6) | 61 (12.8) | |
| Yi | 50 (2.4) | 17 (3.0) | 4 (1.7) | 24 (7.3) | 4 (0.8) | 1 (0.2) | |
| other | 35 (1.7) | 3 (0.5) | 2 (0.9) | 10 (3.0) | 6 (1.3) | 14 (2.9) | |
| Occupation | <0.001 | ||||||
| Farmer | 743 (38.0) | 95 (17.8) | 70 (35.5) | 4 (1.2) | 180 (42.3) | 394 (84.0) | |
| Employed | 323 (16.5) | 105 (19.6) | 46 (23.4) | 41 (12.5) | 106 (24.9) | 25 (5.3) | |
| Unemployed | 889 (45.5) | 335 (62.6) | 81 (41.1) | 283 (86.3) | 140 (32.9) | 50 (10.7) | |
| Marriage status [n (%)] | <0.001 | ||||||
| Single | 909 (43.8) | 275 (48.2) | 107 (46.9) | 140 (42.6) | 193 (41) | 194 (40.5) | |
| Married/live with partner | 916 (44.1) | 242 (42.5) | 105 (46.1) | 134 (40.7) | 232 (49.3) | 203 (42.4) | |
| Divorced | 252 (12.1) | 53 (9.3) | 16 (7) | 55 (16.7) | 46 (9.8) | 82 (17.1) | |
| Education level | |||||||
| None | 141 (6.8) | 48 (8.4) | 12 (5.4) | 7 (2.1) | |||
| Primary | 682 (33.0) | 203 (35.7) | 81 (36.3) | 66 (20.1) | |||
| Secondary | 942 (45.6) | 241 (42.4) | 104 (46.6) | 161 (49.1) | |||
| High school/university | 303 (14.7) | 77 (13.5) | 26 (11.7) | 94 (28.7) | |||
| Age of first drug injection | |||||||
| N(respondents) | 1928 | 555 | 188 | 288 | |||
| mean(95%CI) | 24.7 (24.4,25.0) | 23.5 (23.0,24.0) | 23.1 (22.3,23.9) | 25.2 (24.4,26.0) | |||
| Years of drug injection | |||||||
| N(respondents) | 1936 | 556 | 192 | 288 | |||
| mean(95%CI) | 6.8 (6.6,7.0) | 5.4 (5.0,5.8) | 5.9 (5.2,6.6) | 11.6 (11.0,12.2) | |||
| Main routes of drugs use | |||||||
| Injecting only | 1530 (89.1) | 509 (89.6) | 189 (85.9) | NA | |||
| Non-injecting | 187 (10.9) | 59 (10.4) | 31 (14.1) | NA | |||
| Frequency of drug injection | |||||||
| mean (95%CI) | 3.0 (2.9,3.1) | 2.7 (2.6,2.8) | 3.1 (2.9,3.3) | NA | |||
| ≤1 time/d | 164 (10.0) | 63 (11.3) | 12 (6.2) | NA | |||
| 1–3 times/d | 563(34.4) | 227(40.7) | 73(38) | NA | |||
| ≥3times/d | 910(55.6) | 268(48.0) | 107(55.7) | NA | |||
| Frequency of needles used | <0.001 | ||||||
| mean(95%CI) | 1.9 (1.8,2.0) | 1.6 (1.5,1.7) | 1.5 (1.4,1.6) | NA | 1.6 (1.44,1.68) | 2.6 (2.3, 2.9) | |
| Once | 863 (52.5) | 244 (43.6) | 115 (60.2) | NA | 245 (57.9) | 187 (39.8) | |
| >1 time | 781 (47.5) | 316 (56.4) | 76 (39.8) | NA | 178 (42.1) | 283 (60.2) | |
| Needles/syringes sharing | <0.001 | ||||||
| Yes | 556 (33.7) | 232 (41.3) | 87 (46.0) | NA | 62 (14.5) | 175 (37.1) | |
| No | 1094 (66.3) | 330 (58.7) | 102 (54.0) | NA | 365 (85.5) | 297 (62.9) | |
| NO of sexual partner | <0.01 | ||||||
| mean(95%CI) | 5.2 (4.6,5.8) | 5.6 (4.6,6.6) | 4.6 (3.5,4.7) | NA | 5.7 (4.5,6.9) | 4.6 (3.1,6.1) | |
| 0 | 204(12.6) | 47(9.2) | 39(18.8) | NA | 37(8.3) | 81(17.8) | |
| 1 | 515(31.8) | 128(25) | 47(22.6) | NA | 194(43.4) | 146(32.2) | |
| >1 | 902(55.6) | 337(65.8) | 122(58.7) | NA | 216(48.3) | 227(50) | |
| History of sexual transmission disease | <0.01 | ||||||
| No | 1430(84.2) | 428(76.8) | 153(70.5) | NA | 436(93.8) | 413(89.8) | |
| Yes | 269(15.8) | 129(23.2) | 64(29.5) | NA | 29(6.2) | 47(10.2) |
Note: Numbers may not add up to total because not all participants answered all questions. p 1 value showed the difference among 5 study sites.
NA: not available a: Kruskal-Wallis test.