Description of the effects of setting, age, time and socio-economic status on the number of Chlamydia trachomatis tests†
| N per category | GP (N=6349) | STI clinic (N=4686) | Gynaecology (N=4567) | Chlamydia screening (N=6427) | |||||
|---|---|---|---|---|---|---|---|---|---|
| N | Adj. RR (95% CI) | N | Adj. RR (95% CI) | n | Adj. RR (95% CI) | n | Adj. RR (95% CI) | ||
| Men | |||||||||
| Provider | 5740 | 1478 | 1 (ref)** | 2134 | 1.43 (1.22 to 1.68) | n.a. | n.a. | 2128 | 2.08 (1.72 to 2.51) |
| Age (years) | |||||||||
| 16–21 | 1246 | 269 | 1 (ref)** | 325 | 1 (ref)** | n.a. | n.a. | 652 | 1 (ref)** |
| 22–24 | 1556 | 369 | 2.91 (2.26 to 3.75) | 618 | 3.91 (2.88 to 5.31) | n.a. | n.a. | 569 | 1.81 (1.51 to 2.17) |
| 25–29 | 2938 | 840 | 4.13 (3.18 to 5.35) | 1191 | 4.82 (3.65 to 6.37) | n.a. | n.a. | 907 | 1.81 (1.47 to 2.22) |
| Test year (cont.)‡ | 1.07 (0.99 to 1.16) | 1.14 (1.06 to 1.23) | n.a. | n.a. | 1.4 (1.3 to 1.5) | ||||
| SES§ | n.a. | n.a. | |||||||
| Low | 1952 | 599 | 1.66 (1.32 to 2.08) | 664 | 1.16 (0.91 to 1.48) | n.a. | n.a. | 689 | 1.04 (0.84 to 1.30) |
| Medium | 1925 | 479 | 1.30 (1.04 to 1.64) | 761 | 1.31 (1.02 to 1.68) | n.a. | n.a. | 685 | 1.0 (0.83 to 1.26) |
| High | 1722 | 391 | 1 (ref)** | 618 | 1 (ref) | n.a. | n.a. | 713 | 1 (ref) |
| Women | 3.50 (3.08 to 3.99)¶ | 1.28 (1.11 to 1.47)¶ | n.a. | n.a. | 2.18 (1.95 to 2.42)¶ | ||||
| Provider | 16 289 | 4871 | 1 (ref)** | 2552 | 0.74 (0.60 to 0.91) | 4567 | 0.81 (0.68 to 0.96) | 4299 | 1.56 (1.28 to 1.90) |
| Age (years) | |||||||||
| 16–21 | 4229 | 1326 | 1 (ref)** | 660 | 1 (ref)** | 650 | 1 (ref)** | 1593 | 1 (ref)** |
| 22–24 | 3991 | 1167 | 1.90 (1.55 to 2.32) | 760 | 2.41 (1.92 to 3.01) | 923 | 3.04 (2.43 to 3.83) | 1141 | 1.50 (1.33 to 1.70) |
| 25–29 | 8069 | 2378 | 2.35 (1.97 to 2.79) | 1132 | 2.23 (1.78 to 2.79) | 2994 | 6.02 (4.89 to 7.42) | 1565 | 1.27 (1.12 to 1.45) |
| Test year (cont.)‡ | 1.03 (0.97 to 1.08) | 1.09 (1.02 to 1.17) | 1.00 (0.94 to 1.06) | 1.32 (1.22 to 1.42) | |||||
| SES§ | |||||||||
| Low | 6170 | 1986 | 1.54 (1.32 to 1.80) | 865 | 1.25 (0.99 to 1.56) | 2022 | 1.74 (1.46 to 2.07) | 1297 | 0.93 (0.80 to 1.07) |
| Medium | 5155 | 1508 | 1.18 (0.99 to 1.40) | 861 | 1.25 (1.00 to 1.55) | 1303 | 1.13 (0.95 to 1.34) | 1483 | 1.07 (0.94 to 1.20) |
| High | 4712 | 1335 | 1 (ref)** | 719 | 1 (ref) | 1206 | 1 (ref)** | 1452 | 1 (ref) |
Overall p values for categorical variables were specified by **p<0.01.
†Calculated by means of multivariable Poisson regression analysis, including provider, age, test year and SES, where appropriate. The rows stating ‘Provider’ should be read horizontally and include the analyses of differences in number of tests between providers. Analyses evaluating differences in number of tests by age, test year and SES were stratified per provider and should be read vertically.
‡Range of test years: 2006–2010, except for chlamydia screening: 2008–2010, because chlamydia screening started in 2008.
§The numbers given for the SES categories do not add up to the total number of tests performed because of missing SES data for a proportion of patients.
¶Comparison of Chlamydia trachomatis testing rates between men and women; men are reference category.
Adj. RR, adjusted rate ratio; GP, general practitioner; SES, socio-economic status; STI, sexually transmitted infection.