Distribution of secondary exposure variables by attendance status
| Characteristic | Attended (n=77 743) | Did not attend (n=8306) | P value |
| Age | 53.5 (19.0) | 51.5 (19.1) | <0.001 |
| Sex | |||
| Female | 42 579 (91.0%) | 4216 (9.0%) | <0.001 |
| Male | 35 164 (89.6%) | 4090 (10.4%) | |
| Ethnicity | |||
| Asian (South) | 3827 (93.3%) | 275 (6.7%) | <0.001 |
| Black | 2093 (91.1%) | 204 (8.9%) | |
| Other | 14 621 (91.5%) | 1366 (8.5%) | |
| Unknown | 47 932 (88.9%) | 5962 (11.1%) | |
| White | 9270 (94.9%) | 499 (5.1%) | |
| Socioeconomic deprivation (decile)* | 5 (4) | 4 (3) | <0.001 |
| Broadband access (index) | 3.40 | 3.42 | 0.011 |
| Subspecialty | |||
| Adnexal | 6322 (89.9%) | 707 (10.1%) | <0.001 |
| Cataract | 13 747 (90.6%) | 1431 (9.4%) | |
| General | 32 661 (92.8%) | 2553 (7.2%) | |
| Glaucoma | 10 755 (89.8%) | 1224 (10.2%) | |
| Medical retina | 14 258 (85.6%) | 2391 (14.4%) | |
| Interpreter required | |||
| Yes | 669 (91.3%) | 64 (8.7%) | 0.385 |
| No | 77 074 (90.3%) | 8242 (9.7%) | |
| Diabetes mellitus | |||
| Yes | 3747 (89.3%) | 449 (10.7%) | 0.021 |
| No | 73 996 (90.4%) | 7857 (9.6%) | |
| Time of appointment | |||
| Early morning | 34 519 (89.4%) | 4109 (10.6%) | <0.001 |
| Late morning | 6879 (92.0%) | 599 (8.0%) | |
| Early afternoon | 28 031 (90.3%) | 3025 (9.7%) | |
| Late afternoon | 8314 (93.6%) | 573 (6.4%) | |
| Registered sight-impaired | |||
| Yes | 469 (94.9%) | 25 (5.1%) | <0.001 |
| No | 77 274 (90.3%) | 8281 (9.7%) | |
| Previous cancellation | |||
| No | 66 012 (91.2%) | 6365 (8.8%) | <0.001 |
| By hospital | 8435 (86.2%) | 1354 (13.8%) | |
| By patient | 3296 (84.9%) | 587 (15.1%) |
*Missing values from 216 individuals (0.3% of the dataset).