Background
Methods
Participants and Recruitment
Selected outcomes
Model | Outcome* | Comparison group |
---|---|---|
1. | Chlamydia, NO selected STI | respondents not reporting any selected STI |
2. | gonorrhoea or gonorrhoea AND any selected STI | respondents not reporting any selected STI |
3. | HIV infection or HIV infection AND any selected STI** | respondents not reporting any selected STI |
Pilot study
Data collection
Measures and data presentation
Demographic characteristics | respondents N = 2430 (%) | Chlamydia* N= 101 (%) | Crude PR Chlamydia [95% CI] | gonorrhoea N = 35 (%) | Crude PR gonorrhoea [95% CI] | HIV N = 42 (%) | Crude PR HIV [95% CI] | Syphilis N = 17 (%) | Crude PR syphilis |
---|---|---|---|---|---|---|---|---|---|
age groups (years) | |||||||||
16-25 | 768 (31.6) | 37 (36.6) | ref. group | 16 (45.7) | ref. group | 7 (16.7) | ref. group | 3 (17.6) | ref. group |
26-35 | 769 (31.6) | 35 (34.6) | 0.9 [0.6-1.5] | 8 (22.9) | 0.5 [0.2-1.2] | 15 (35.7) | 2.1 [0.9-5.2] | 6 (35.3) | 2.0 [0.5-8.0] |
36-45 | 551 (22.7) | 22 (21.8) | 0.8 [0.5-1.4] | 8 (22.9) | 0.7 [0.3-1.6] | 11 (26.2) | 2.2 [0.8-5.6] | 5 (29.4) | 2.3 [0.6-10.0] |
≥ 46 | 342 (14.0) | 7 (6.9) | 0.4 [0.2-0.9] | 3 (8.6) | 0.4 [0.1-1.4] | 9 (21.4) | 2.9 [1.1-7.7] | 3 (17.6) | 2.2 [0.4-11.1] |
health region of residence | |||||||||
East | 1415 (58.2) | 70 (69.3) | ref. group | 26 (74.3) | ref. group | 36 (85.7) | ref. group | 15 (88.2) | ref. group |
West | 369 (15.2) | 16 (15.8) | 0.9 [0.5-1.5] | 5 (14.3) | 0.7 [0.3-1.9] | 1 (2.4) | 0.1 [0.0-0.8] | 0 | |
South | 254 (10.4) | 7 (6.9) | 0.6 [0.3-1.2] | 2 (5.7) | 0.4 [0.1-1.8] | 2 (4.8) | 0.3 [0.1-1.3] | 2 (11.8) | 0.7 [0.2-3.2] |
Mid-Norway | 236 (9.7) | 7 (6.9) | 0.6 [0.3-1.3] | 2 (5.7) | 0.5 [0.1-1.9] | 1 (2.4) | 0.2 [0.0-1.2] | 0 | |
North | 151 (6.2) | 1 (1.0) | 0.1 [0.2-0.9] | 0 | 2 (4.8) | 0.5 [0.1-2.1] | 0 | ||
unknown | 5 (0.2) | 0 | 0 | 0 | 0 | ||||
residing in Oslo/Akershus county | |||||||||
no | 1200 (49.4) | 38 (37.6) | ref. group | 11 (31.4) | ref. group | 10 (23.8) | ref. group | 4 (23.5) | ref. group |
yes | 1225 (50.4) | 63 (62.4) | 1.6 [1.1-2.4] | 24 (68.6) | 2.1 [1.0-4.3] | 32 (76.2) | 3.1 [1.5-6.3] | 13 (11.8) | 3.1 [1.5-6.3] |
unknown | 5 (0.2) | 0 | 0 | 0 | 0 | ||||
ethnic background: | |||||||||
Norwegian | 2265 (93.2) | 95 (94.1) | ref. group | 30 (85.7) | ref. group | 37 (88.1) | ref. group | 13 (76.5) | ref. group |
western background | 90 (3.7) | 1 (1.0) | 0.3 [0.0-1.9] | 2 (5.7) | 1.7 [0.4-6.9] | 1 (2.4) | 0.7 [0.1-4.9] | 1 (5.9) | 1.9 [0.2-14.6] |
non-western background | 41 (1.7) | 5 (4.9) | 2.9 [1.2-6.8] | 1 (2.9) | 1.8 [0.3-13.2] | 3 (7.1) | 4.5 [1.4-13.9] | 2 (11.8) | 8.5 [2.0-36.5] |
unknown | 34 (1.4) | 0 | 2 (5.7) | 4.4 [1.1-17.8] | 1 (2.4) | 1.8 [0.2-12.7] | 1 (5.9) | 5.1 [0.7-38.1] | |
education | |||||||||
primary school or less | 121 (5.0) | 6 (5.9) | ref. group | 2 (5.7) | ref. group | 1 (2.4) | ref. group | 1 (5.9) | ref. group |
secondary school | 903 (37.2) | 36 (35.6) | 0.8 [0.3-1.9] | 16 (45.7) | 1.1 [0.3-4.6] | 15 (35.7) | 2.0 [0.3-15.1] | 5 (29.4) | 0.7 [0.1-5.7] |
high school/university | 1401 (57.6) | 59 (58.4) | 0.8 [0.4-1.9] | 17 (48.6) | 0.7 [0.2-3.1] | 26 (62) | 2.2 [0.3-16.4] | 11 (64.7) | 0.9 [0.1-7.3] |
unknown | 5 (0.2) | 0 | 0 | 0 | 0 | ||||
income before tax in 1000 NOK** in 2005 | |||||||||
< 150 | 670 (27.6) | 24 (23.8) | ref. group | 12 (34.3) | ref. group | 5 (11.9) | ref. group | 4 (23.5) | ref. group |
150-299 | 573 (23.6) | 22 (21.8) | 1.1 [0.6-1.9] | 11 (31.4) | 1.1 [0.5-2.4] | 8 (19.0) | 1.9 [0.6-5.7] | 4 (23.5) | 1.2 [0.3-4.6] |
300-500 | 854 (35.3) | 37 (36.6) | 1.2 [0.7-2.0] | 3 (8.6) | 0.2 [0.1-0.7] | 18 (42.9) | 2.8 [1.0-7.6] | 4 (23.5) | 0.9 [0.2-3.2] |
> 500 | 323 (13.3) | 18 (17.8) | 1.5 [0.9-2.8] | 8 (22.9) | 1.4 [0.6-3.3] | 10 (23.8) | 4.1 [1.2-12.0] | 5 (29.4) | 2.6 [0.7-9.6] |
unknown | 10 (0.4) | 0 | 1 (2.9) | 5.6 [0.8-38.9] | 1 (2.4) | 13.4 [1.7-104.5] | 0 |
Sexual behaviour | respondents N = 2430 (%) | Chlamydi a* N= 101 (%) | Crude PR Chlamydia [95% CI] | gonorrhoea N = 35 (%) | Crude PR gonorrhoea [95% CI] | HIV N = 42 (%) | Crude PR HIV [95% CI] | Syphilis N = 17 (%) | Crude PR syphilis [95% CI] |
---|---|---|---|---|---|---|---|---|---|
sexual orientation | |||||||||
homosexual | 2088 (85.9) | 89 (88.1) | ref. group | 30 (85.7) | ref. group | 37 (88.1) | ref. group | 15 (88.2) | ref. group |
bisexual | 225 (9.3) | 8 (7.9) | 0.8 [0.4-1.7] | 4 (11.4) | 1.2 [0.4-3.5] | 3 (7.1) | 0.7 [0.2-2.4] | 1 (5.9) | 0.6 [0.1-4.7] |
heterosexual | 77 (3.2) | 3 (3.0) | 0.9 [0.3-2.8] | 1 (2.9) | 0.9 [0.1-6.5] | 2 (4.8) | 1.5 [0.4-6.0] | 1 (5.9) | 1.8 [0.2-13.5] |
unsure | 40 (1.6) | 1 (1.0) | 0.6 [0.1-4.1] | 0 | 0 | 0 | |||
N of male sexual partners in life | |||||||||
1 | 68 (2.8) | 0 | 1 (2.9) | ref. group | 1 (2.4) | ref. group | 1 (5.9) | ref. group | |
2-5 | 334 (13.7) | 3 (3.0) | ref. group | 0 | 0 | 0 | |||
6-10 | 383 (15.8) | 6 (5.9) | 1.7 [0.4-6.9] | 3 (8.6) | 0.5 [0.1-5.0] | 1 (2.4) | 0.2 [0.0-2.8] | 0 | |
11-50 | 868 (35.7) | 40 (39.6) | 5.1 [1.6-16.5] | 11 (31.4) | 0.9 [0.1-6.6] | 9 (21.4) | 0.7 [0.1-5.5] | 5 (29.4) | 0.4 [0.0-3.3] |
51- > 500 | 777 (32.0) | 52 (51.5) | 7.4 [2.3-23.7] | 20 (57.1) | 1.7 [0.2-12.8] | 31 (73.8) | 2.7 [0.4-19.6] | 11 (64.7) | 1.0 [0.1-7.3] |
N of male sexual partners in the past 6 months | |||||||||
0 | 175 (7.2) | 2 (2.0) | ref. group | 0 | 3 (7.1) | ref. group | 0 | ||
1-2 | 978 (40.2) | 21 (20.8) | 1.9 [0.4-8.1] | 6 (17.1) | ref. group | 12 (28.6) | 0.7 [0.2-2.5] | 5 (29.4) | ref. group |
3-5 | 649 (26.7) | 29 (28.7) | 4.0 [1.0-16.5] | 9 (25.7) | 2.3 [0.8-6.3] | 9 (21.4) | 0.8 [0.2-3.0] | 4 (23.5) | 1.2 [0.3-4.5] |
6-10 | 383 (15.8) | 24 (23.8) | 5.6 [1.3-23.3] | 11 (31.4) | 4.7 [1.7-12.6] | 6 (14.3) | 0.9 [0.2-3.7] | 3 (17.6) | 1.5 [0.4-6.4] |
> 10 | 242 (10.0) | 25 (24.8) | 9.2 [2.2-38.3] | 9 (25.7) | 6.1 [2.2-16.9] | 12 (28.6) | 2.9 [0.8-10.3] | 5 (29.4) | 4.4 [1.2-13.8] |
unknown | 3 (0.1) | 0 | 0 | 0 | 0 | ||||
anony mous/casual partner in the last 6 months | |||||||||
no | 853 (35.1) | 20 (19.8) | ref. group | 6 (17.1) | ref. group | 12 (28.6) | ref. group | 1 (5.9) | ref. group |
yes | 1572 (64.7) | 81 (80.2) | 2.2 [1.3-3.6] | 29 (82.9) | 2.6 [1.1-6.3] | 30 (71.4) | 1.3 [0.7-2.6] | 16 (94.1) | 8.7 [1.1-65.3] |
unknown | 5 (0.2) | 0 | 0 | 0 | 0 | ||||
UAI** with anonymous/casual partner in the last 6 months | |||||||||
no | 1848 (76.0) | 52 (51.5) | ref. group | 19 (54.3) | ref. group | 24 (57.1) | ref. group | 10 (58.8) | ref. group |
yes | 576 (23.7) | 49 (48.5) | 3.0 [2.1-4.4] | 16 (45.7) | 2.7 [1.4-5.2] | 18 (42.9) | 2.4 [1.3-4.4] | 7 (41.2) | 2.2 [0.9-5.9] |
unknown | 6 (0.2) | 0 | 0 | 0 | 0 | ||||
practice of threesome or group sex | |||||||||
no | 1270 (52.3) | 32 (31.7) | ref. group | 14 (40.0) | ref. group | 13 (30.9) | ref. group | 7 (41.2) | ref. group |
yes | 1068 (43.9) | 66 (65.3) | 2.4 [1.6-3.7] | 21 (60.0) | 1.8 [0.9-3.5] | 27 (64.3) | 2.5 [1.3-4.8] | 9 (52.9) | 1.6 [0.6-4.1] |
unknown | 92 (3.8) | 3 (3.0) | 1.3 [0.4-4.1] | 0 | 2 (4.8) | 2.1 [0.5-9.3] | 1 (5.9) | 2.0 [0.2-15.9] | |
received money for sex in the last year | |||||||||
no | 2343 (96.4) | 93 (92.1) | ref. group | 29 (82.9) | ref. group | 40 (95.2) | ref. group | 16 (94.1) | ref. group |
yes | 78 (3.2) | 7 (6.9) | 2.3 [1.1-4.7] | 6 (17.1) | 6.2 [2.7-14.5] | 2 (4.8) | 1.5 [0.4-6.1] | 1 (5.9) | 1.9 [0.2-14.0] |
unknown | 9 (0.4) | 1 (1.0) | 2.8 [0.4-17.9] | 0 | 0 | 0 | |||
paid for sex in the last year | |||||||||
no | 2305 (94.9) | 90 (89.1) | ref. group | 29 (82.9) | ref. group | 39 (92.9) | ref. group | 16 (94.1) | ref. group |
yes | 118 (4.9) | 11 (10.9) | 2.4 [1.3-4.3] | 5 (14.3) | 3.4 [1.3-8.5] | 3 (7.1) | 1.5 [0.5-4.8] | 1 (5.9) | 1.2 [0.2-9.1] |
unknown | 7 (0.3) | 0 | 1 (2.9) | 11.3 [1.8-72.2] | 0 | 0 | |||
how many times feeling drunk in a given month | |||||||||
< 1 | 487 (20.0) | 8 (7.9) | ref. group | 2 (5.7) | ref. group | 10 (23.8) | ref. group | 4 (23.5) | ref. group |
1 | 416 (17.1) | 14 (13.9) | 2.0 [0.9-4.8] | 9 (25.7) | 5.3 [1.1-24.2] | 12 (28.6) | 1.4 [0.6-3.2] | 4 (23.5) | 1.2 [0.3-4.6] |
2-3 | 588 (24.2) | 27 (26.7) | 2.8 [1.3-6.1] | 12 (34.3) | 5.0 [1.1-22.1] | 12 (28.6) | 1.0 [0.4-2.3] | 3 (17.6) | 0.6 [0.1-2.8] |
≥ 4 | 923 (38.0) | 52 (51.5) | 3.4 [1.6-7.2] | 12 (34.3) | 3.2 [0.7-14.1] | 8 (19.0) | 0.4 [0.2-1.1] | 5 (29.4) | 0.6 [0.2-2.4] |
unknown | 16 (0.7) | 0 | 0 | 0 | 1 (5.9) | 7.6 [0.9-64.3] | |||
unsafe sex under the influence of alcohol in the past 12 months | |||||||||
no | 1729 (71.1) | 49 (48.5) | ref. group | 18 (51.4) | ref. group | 27 (64.3) | ref. group | 11 (64.7) | ref. group |
yes | 641 (26.4) | 51 (50.5) | 2.8 [1.9-4.1] | 17 (48.6) | 2.5 [1.3-4.9] | 15 (35.7) | 1.5 [0.8-2.8] | 6 (35.3) | 1.5 [0.5-4.0] |
unknown | 60 (2.5) | 1 (1.0) | 0.6 [0.1-4.2] | 0 | 0 | 0 | |||
under the influence of selected drugs*** during sex in the past 12 months | |||||||||
no | 2106 (86.7) | 81 (83.2) | ref. group | 25 (71.4) | ref. group | 25 (59.5) | ref. group | 14 (82.3) | ref. group |
yes | 240 (9.9) | 17 (16.8) | 1.8 [1.1-3.0] | 10 (28.6) | 3.6 [1.8-7.5] | 16 (38.1) | 5.6 [3.0-10.4] | 3 (17.6) | 1.9 [0.5-6.5] |
unknown | 84 (3.5) | 3 (3.0) | 0.9 [0.3-2.9] | 0 | 1 (2.4) | 1.0 [0.1-7.3] | 0 | ||
current steady relationship with a woman | |||||||||
no | 2113 (86.9) | 89 (88.1) | ref. group | 28 (80.0) | ref. group | 36 (85.7) | ref. group | 13 (76.5) | ref. group |
yes | 236 (9.7) | 10 (9.9) | 1.0 [0.5-1.9] | 4 (11.4) | 1.2 [0.4-3.6] | 5 (11.9) | 1.2 [0.5-3.1] | 3 (17.6) | 2.1 [0.6-7.2] |
unknown | 81 (3.3) | 2 (2.0) | 0.6 [0.1-2.3] | 3 (8.6) | 2.8 [0.9-9.0] | 1 (2.4) | 0.7 [0.1-5.2] | 1(5.9) | 2.0 [0.3-15.1] |
current steady relationship with a man | |||||||||
no | 1492 (61.4) | 65 (64.4) | ref. group | 19 (54.3) | ref. group | 26 (61.9) | ref. group | 8 (47.1) | ref. group |
yes | 936 (38.5) | 36 (35.6) | 0.9 [0.6-1.3] | 16 (46.7) | 1.3 [0.7-2.6] | 16 (38.1) | 1.0 [0.5-1.8] | 9 (52.9) | 1.8 [0.7-4.6] |
unknown | 2 (0.1) | 0 | 0 | 0 | 0 | ||||
ever had a date in reality with an Internet partner | |||||||||
no | 190 (7.8) | 3 (3.0) | ref. group | 0 | no variance | 2 (4.8) | ref. group | 1 (5.9) | ref. group |
yes | 2209 (90.9) | 97 (96.0) | 2.8 [0.9-8.7] | 35 (100) | 40 (95.2) | 1.7 [0.4-7.1] | 16 (94.1) | 1.4 [0.2-10.3] | |
unknown | 31 (1.3) | 1 (1.0) | 2.0 [0.2-19.0] | 0 | 0 | 0 |
Potential risk factors | Chlamydia N = 101 | gonorrhoea N = 35 | HIV N = 42 | |||
---|---|---|---|---|---|---|
Adjusted PR [95% CI] | p for trend | Adjusted PR [95% CI] | p for trend | Adjusted PR [95% CI] | p for trend | |
age groups (years) | 0.002 | 0.255 | 0.932 | |||
16-25 | ref. group | ref. group | ref. group | |||
26-35 | 0.6 [0.4-1.1] | 0.5 [0.2-1.6] | 1.4 [0.6-3.2] | |||
36-45 | 0.4 [0.2-0.9] | 0.7 [0.2-2.3] | 0.8 [0.3-2.1] | |||
≥ 46 | 0.3 [0.1-0.7] | 0.6 [0.1-2.2] | 1.5 [0.6-3.8] | |||
residing in Oslo or Akershus county | ||||||
no | ref. group | ref. group | ref. group | |||
yes | 1.4 [1.0-2.1] | 1.9 [0.9-4.1] | 2.3 [1.2-4.6] | |||
ethnic background: | ||||||
Norwegian | ref. group | ref. group | ref. group | |||
immigrant with western background | 0.3 [0.0-1.8] | 1.5 [0.4-6.1] | 0.4 [0.0-3.0] | |||
immigrant with non-western background | 2.8 [1.4-5.7] | 1.8 [0.5-6.1] | 5.4 [1.9-15.3] | |||
unknown | not included | 5.9 [1.3-26.3] | not included | |||
education | 0.568 | 0.987 | not | |||
primary school or less | ref. group | ref. group | merged with ref. group | calculated | ||
secondary school | 0.6 [0.3-1.2] | 1.7 [0.2-16.1] | ref. group | |||
high school/university | 0.5 [0.3-1.1] | 1.6 [0.1-16.5] | 0.8 [0.5-1.5] | |||
annual income before tax in 1000 NOK* in 2005 | 0.204 | 0.380 | 0.102 | |||
< 150 | ref. group | ref. group | ref. group | |||
150-299 | 1.1 [0.6-1.9] | 1.0 [0.4-2.5] | 1.0 [0.4-2.7] | |||
300-500 | 1.2 [0.6-2.1] | 0.1 [0.0-0.6] | 0.8 [0.3-1.9] | |||
> 500 | 1.3 [0.6-2.9] | 1.0 [0.3-2.9] | 1.5 [0.6-4.3] | |||
unknown | not included | not included | 10.4 [1.5-71.4] | |||
N of male sexual partners in life: | < 0.001 | 0.056 | < 0.001 | |||
1-10 | ref. group | ref. group | ref. group | |||
11-50 | 4.0 [1.8-8.8] | 2.4 [0.7-7.6] | 3.0 [0.7-13.2] | |||
51- > 500 | 4.4 [1.9-10.3] | 4.5 [1.3-15.6] | 13.9 [3.5-55.8] | |||
N of male sexual partners in the past 6 months | 0.308 | 0.065 | 0.544 | |||
0-2 | ref. group | ref. group | ref. group | |||
3-5 | 1.2 [0.6-2.2] | 1.7 [0.6-4.9] | 0.6 [0.2-1.8] | |||
6-10 | 1.2 [0.7-2.3] | 3.1 [1.1-8.8] | 0.4 [0.1-1.5] | |||
> 10 | 1.6 [0.8-3.2] | 3.4 [1.0-11.3] | 0.7 [0.2-2.3] | |||
practice of threesome or group sex | ||||||
no | ref. group | ref. group | ref. group | |||
yes | 1.5 [1.0-2.3] | 0.8 [0.4-1.7] | 1.0 [0.5-2.1] | |||
received money for sex in the last year | ||||||
no | ref. group | ref. group | ref. group | |||
yes | 0.9 [0.3-2.2] | 2.3 [0.7-8.4] | 1.9 [0.4-8.3] | |||
paid for sex in the last year | ||||||
no | ref. group | ref. group | ref. group | |||
yes | 1.6 [0.8-3.2] | 1.2 [0.3-3.9] | 0.6 [0.1-2.2] | |||
unknown | not included | 5.5 [0.4-82.7] | not included | |||
how many times feeling drunk in a given month | 0.409 | 0.283 | < 0.001 | |||
< 1 | ref. group | ref. group | ref. group | |||
1 | 1.6 [0.7-4.0] | 3.9 [0.9-16.8] | 1.1 [0.4-2.7] | |||
2-3 | 2.0 [0.9-4.5] | 3.3 [0.8-12.9] | 0.6 [0.2-1.3] | |||
≥ 4 | 1.6 [0.7-3.5] | 1.3 [0.3-5.0] | 0.1 [0.0-0.3] | |||
unsafe sex under the influence of alcohol in the past 12 months | ||||||
no | ref. group | ref. group | ref. group | |||
yes | 1.8 [1.1-2.9] | 1.9 [0.9-4.3] | 1.5 [0.7-3.4] | |||
under the influence of selected drugs** during sex in the past 12 months | ||||||
no | ref. group | ref. group | ref. group | |||
yes | 0.8 [0.5-1.5] | 1.7 [0.8-3.9] | 5.2 [2.7-11.4] | |||
ever had a date in reality with Internet partner | ||||||
no | ref. group | not included | ref. group | |||
yes | 1.6 [0.5-5.0] | 1.4 [0.4-4.6] | ||||
UAI*** with a casual or anonymous partner in the last 6 months | ||||||
no | ref. group | ref. group | ref. group | |||
yes | 1.5 [0.9-2.4] | 1.0 [0.5-2.2] | 2.0 [0.9-4.6] |