Table 1. Demographic and baseline characteristics of the participants by study phase.
| Characteristic at screening | Study phase | Total | ||
|---|---|---|---|---|
| Baseline | Longer-turnaround | Rapid | ||
| N HOCI cases | 850 | 373 | 947 | 2170 |
| N HOCI cases per site, median (range); N sites | 36 (1–207); 14 | 19 (0–86); 13 | 30.5 (4-297); 14 | 103.5 (40-451); 14 |
| HAI classification, n (%) | ||||
| Indeterminate (3–7 days) | 362 (42.6) | 166 (44.5) | 371 (39.2) | 899 (41.4) |
| Probable (8–14 days) | 236 (27.8) | 121 (32.4) | 270 (28.5) | 627 (28.9) |
| Definite (>14 days) | 252 (29.6) | 86 (23.1) | 306 (32.3) | 644 (29.7) |
| Age (years), median (IQR, range) | 77.5 (65.4–85.6, 0.4–100.5) | 77.6 (64.6–86.7, 0.7–100.7) | 76.4 (62.6–85.5, 0.6–103.5) | 76.7 (64.4–85.6, 0.4–103.5) |
| Age ≥70 years, n/N (%) | 589/850 (69.3) | 240/373 (64.3) | 598/947 (63.1) | 1427/2170 (65.8) |
| Sex at birth: female, n/N (%) | 457/850 (53.8) | 177/372 (47.6) | 460/947 (48.6) | 1094/2169 (50.4) |
| Ethnicity, n (%) | ||||
| White | 668 (78.6) | 275 (73.7) | 732 (77.3) | 1675 (77.2) |
| Mixed ethnicity | 9 (1.1) | 6 (1.6) | 8 (0.8) | 23 (1.1) |
| Asian | 46 (5.4) | 26 (7.0) | 34 (3.6) | 106 (4.9) |
| Black Caribbean or African | 36 (4.2) | 18 (4.8) | 46 (4.9) | 100 (4.6) |
| Other | 6 (0.7) | 1 (0.3) | 4 (0.4) | 11 (0.5) |
| Unknown | 85 (10.0) | 47 (12.6) | 123 (13.0) | 255 (11.8) |
| Symptomatic at time of sampling, n/N (%) | 167/739 (22.6) | 58/322 (18.0) | 106/659 (16.1) | 331/1720 (19.2) |
| Significant comorbidity present, n/N (%) | 650/776 (83.8) | 260/323 (80.5) | 574/757 (75.8) | 1484/1856 (80.0) |
| Pregnant, n/N (%) | 6/451 (1.3) | 1/177 (0.6) | 4/445 (0.9) | 11/1073 (1.0) |
| Hospital admission route, n (%) | ||||
| Emergency department | 605 (71.2) | 258 (69.2) | 549 (58.0) | 1412 (65.1) |
| Hospital transfer | 59 (6.9) | 21 (5.6) | 51 (5.4) | 131 (6.0) |
| Care home | 3 (0.4) | 0 (0) | 0 (0) | 3 (0.1) |
| GP referral | 38 (4.5) | 15 (4.0) | 76 (8.0) | 129 (5.9) |
| Outpatient clinic ref. | 27 (3.2) | 20 (5.4) | 30 (3.2) | 77 (3.5) |
| Other | 42 (4.9) | 9 (2.4) | 48 (5.1) | 99 (4.6) |
| Unknown | 76 (8.9) | 50 (13.4) | 193 (20.4) | 319 (14.7) |
GP, general practitioner; HAI, hospital-acquired infection; HOCI, hospital-onset COVID-19 infection.