Table 2

 Characteristics and risk factors for chlamydial infection among men and women opportunistically screened outside GUM clinics, National Chlamydia Screening Programme in England, 1 April 2003–31 March 2004

Total tests No (col %)Screening tests among womenScreening tests among men
No No (%) CT+Unadjusted OR (95% CI)Adjusted OR** (95% CI)No No (%) CT+Unadjusted OR (95% CI)Adjusted OR†† (95% CI)
CT+, Chlamydia trachomatis positive; OR, odds ratio; CI, confidence interval; PCR, polymerase chain reaction; SDA, strand displacement assay; TMA, transcription mediated assay; LCR, ligase chain reaction; NA, not applicable.
*Statistically significant at p <0.05 level.
†Statistically significant at p <0.001 level.
**Female model includes females under 25 years of age, ethnicity, behavioural risks, specimen type, and laboratory test.
††Male model includes 16–24 year old men only, ethnicity, behavioural risks, and laboratory test.
‡Only people responding to the question are included in totals.
§Includes gynaecology, infertility, colposcopy, and antenatal services.
¶Includes chlamydia screening office, outreach activities, and unknown clinic types.
Total 16 41315 2411538 (10.1%)model n = 10 0411172156 (13.3%)model n = 792
Age
    Under 16 years1349 (8.2)128496 (7.5%)0.84 (0.67 to 1.05)referent651 (1.5%)0.06 (0.01 to 0.46)*not in model
    16–19 years7201 (43.9)6544792 (12.1%)1.43 (1.28 to 1.60)†1.85 (1.41 to 2.42)†65766 (10.0%)0.45 (0.32 to 0.64)†referent
    20–24 years7863 (47.9)7413650 (8.8%)referent1.38 (1.04 to 1.82)*45089 (19.8%)referent2.51 (1.64 to 3.86)†
Ethnicity
    White11 138 (67.9)10 286973 (9.5%)referentreferent85294 (11.0%)referentreferent
    Black Caribbean413 (2.5)36566 (18.1%)2.11 (1.61 to 2.78)†2.04 (1.50 to 2.76)†4814 (29.2%)3.32 (1.72 to 6.41)†2.76 (1.29 to 5.93)*
    Black African408 (2.5)37337 (9.9%)1.05 (0.75 to 1.49)1.10 (0.76 to 1.60)357 (20.0%)2.02 (0.86 to 4.74)1.45 (0.54 to 3.91)
    Black British/other380 (2.3)31648 (15.2%)1.71 (1.25 to 2.35)†1.77 (1.28 to 2.46)†6413 (20.3%)2.06 (1.08 to 3.92)*1.45 (0.69 to 3.04)
    Asian subcontinent262 (1.6)25315 (5.9%)0.60 (0.36 to 1.02)0.84 (0.49 to 1.43)91 (11.1%)1.01 (0.13 to 8.15)0
    Chinese/other Asian201 (1.2)19313 (6.7%)0.69 (0.39 to 1.22)0.81 (0.42 to 1.55)80 (0.0%)00
    Other ethnic group210 (1.3)20213 (6.4%)0.66 (0.37 to 1.16)1.12 (0.61 to 2.05)81 (12.5%)1.15 (0.14 to 9.47)0
    Mixed517 (3.1)49173 (14.9%)1.67 (1.29 to 2.16)†1.59 (1.20 to 2.09)†268 (30.8%)3.58 (1.52 to 8.47)*2.72 (1.01 to 7.31)*
    Unknown2884 (17.6)2762300 (10.9%)1.17 (1.02 to 1.34)*1.25 (0.88 to 1.78)12218 (14.8%)1.40 (0.81 to 2.41)0.85 (0.24 to 3.04)
Risk behaviours‡
    New sex partner
        Yes5077 (45.0)4583586 (12.8%)1.69 (1.48 to 1.92)†1.32 (1.14 to 1.53)†49474 (15.0%)1.43 (0.95 to 2.14)1.14 (0.71 to 1.84)
        No6207 (55.0)5825466 (8.0%)referentreferent38242 (11.0%)referentreferent
    2 or more sex partners
        Yes5061 (45.8)4547589 (13.0%)1.78 (1.56 to 2.03)†1.57 (1.35 to 1.82)†51476 (14.8%)1.47 (0.96 to 2.24)1.23 (0.76 to 1.99)
        No5994 (54.2)5654436 (7.7%)referentreferent34036 (10.6%)referentreferent
Specimen type
    Urine9799 (59.7)8627899 (10.4%)referentreferent1172156 (13.3%)NANA
    Cervical swab2101 (12.8)2101217 (10.3%)0.99 (0.85 to 1.16)1.22 (1.00 to 1.48)
    Vulvo-vaginal swab4513 (27.5)4513422 (9.4%)0.89 (0.79 to 1.00)1.16 (0.98 to 1.37)
Laboratory test
    PCR7041 (42.9)6384542 (8.5%)referentreferent65763 (9.6%)referentreferent
    SDA7629 (46.5)7169828 (11.5%)1.41 (1.26 to 1.58)†1.49 (1.28 to 1.75)†46086 (18.7%)2.17 (1.53 to 3.08)†2.11 (1.33 to 3.35)†
    TMA813 (5.0)78370 (8.9%)1.06 (0.82 to 1.37)not in model305 (16.7%)1.89 (0.70 to 5.10)not in model
    LCR930 (5.7)90598 (10.8%)1.31 (1.04 to 1.64)*not in model252 (8.0%)0.82 (0.19 to 3.56)not in model
Quarter
    Apr–Jun 20031032 (6.3)1015115 (11.3%)referentnot in model171 (5.9%)referentnot in model
    Jul–Sep 20032408 (14.7)2316250 (10.8%)0.95 (0.75 to 1.20)9221 (22.8%)4.73 (0.59 to 37.81)
    Oct–Dec 20035301 (32.3)5013492 (9.8%)0.85 (0.69 to 1.06)28838 (13.2%)2.43 (0.31 to 18.87)
    Jan–Mar 20047672 (46.7)6897681 (9.9%)0.86 (0.70 to 1.06)77596 (12.4%)2.26 (0.30 to 17.25)
Clinic type (no of venues)
    Contraceptive clinics (96)10 316 (62.9)97871068 (10.9%)referentnot in model529106 (20.0%)referentnot in model
    General practices (131)1697 (10.3)1615161 (10.0%)0.90 (0.76–1.08)829 (11.0%)0.49 (0.24 to 1.02)
    Women’s clinics§ (21)218 (1.3)21817 (7.8%)0.69 (0.42 to 1.14)000
    Termination of pregnancy (5)378 (2.3)37639 (10.4%)0.95 (0.67 to 1.32)000
    College, university, school (15)801 (4.9)50025 (5.0%)0.43 (0.29 to 0.65)†30114 (4.7%)0.20 (0.11 to 0.35)†
    Military facilities (4)84 (0.5)284 (14.3%)1.36 (0.47 to 3.93)569 (16.1%)0.76 (0.36 to 1.61)
    Young people’s (16)1987 (12.1)1830150 (8.2%)0.73 (0.61 to 0.87)†15712 (7.6%)0.33 (0.18 to 0.62)†
    Other¶ (14)934 (5.7)88774 (8.3%)0.74 (0.58 to 0.95)*476 (12.8%)0.58 (0.24 to 1.41)