Table 6.
Unweighted negative binomial regression analyses (95% confidence intervals [CI]) of number of contacts on the previous day.
| Variable | N: mean (SD) contacts | Univariable | Multivariable | ||
|---|---|---|---|---|---|
| IRR (95% CI) | p-value | IRR (95% CI) | p-value | ||
| Age 17–24 | 857: 6.4 (18.3) | Reference | NA | Reference | NA |
| Age 25–44 | 368: 4.5 (10.6) | 0.71 (0.62, 0.81) | < 0.001 | 0.54 (0.45, 0.66) | < 0.001 |
| Age 45–64 | 27: 3.7 (4.4) | 0.57 (0.37, 0.88) | 0.011 | 0.29 (0.18, 0.47) | < 0.001 |
| Age 65–79 | 9: 1.6 (1.0) | 0.24 (0.10, 0.56) | 0.001 | 0.34 (0.13, 0.90) | 0.029 |
| Female/other | 893: 5.5 (15.9) | Reference | NA | Reference | NA |
| Male | 368: 6.5 (16.7) | 1.18 (1.03, 1.34) | 0.014 | 1.16 (1.01, 1.35) | 0.038 |
| Undergrad | 725: 6.0 (11.1) | Reference | NA | Reference | NA |
| Postgrad | 536: 5.5 (21.2) | 0.92 (0.81, 1.04) | 0.171 | 0.76 (0.58, 1.00) | 0.052 |
| Study year 1 | 260: 4.4 (8.0) | Reference | NA | Reference | NA |
| Study year 2 | 205: 7.5 (10.8) | 1.71 (1.40, 2.09) | < 0.001 | 1.11 (0.84, 1.46) | 0.456 |
| Study year 3 | 156: 4.7 (8.9) | 1.08 (0.87, 1.35) | 0.480 | 0.76 (0.56, 1.02) | 0.065 |
| Study year 4 + | 640: 6.0 (20.7) | 1.38 (1.18, 1.62) | < 0.001 | 1.45 (1.08, 1.95) | 0.013 |
| No symptoms | 833: 5.6 (17.8) | Reference | NA | Reference | NA |
| Symptoms | 428: 6.2 (12.5) | 1.11 (0.98, 1.26) | 0.100 | 1.26 (1.09, 1.45) | 0.002 |
| No cardinal symptoms | 1186: 5.7 (15.8) | Reference | NA | Reference | NA |
| Cardinal symptoms | 75: 7.3 (21.3) | 1.38 (1.00, 1.64) | 0.052 | 1.62 (1.17, 2.24) | 0.003 |
| Not isolated last week | 1087: 6.0 (16.9) | Reference | NA | Reference | NA |
| Isolated last week | 167: 4.3 (10.6) | 0.71 (0.60, 0.85) | < 0.001 | 0.61 (0.48, 0.76) | < 0.001 |
| Not high risk | 1113: (5.8 (16.3) | Reference | NA | Reference | NA |
| High risk | 148: 5.8 (14.9) | 1.02 (0.84, 1.22) | 0.874 | 1.00 (0.81, 1.22) | 0.984 |
| Household size 1 | 227: 5.9 (16.9) | 1.07 (0.90, 1.28) | 0.420 | 1.24 (1.03, 1.50) | 0.026 |
| Household size 2–3 | 449: 5.5 (11.9) | Reference | NA | Reference | NA |
| Household size 4–5 | 323: 7.2 (23.8) | 1.31 (1.12, 1.53) | 0.001 | 1.36 (1.15, 1.61) | < 0.001 |
| Household size 6–9 | 153: 5.7 (9.6) | 1.04 (0.85, 1.26) | 0.733 | 1.27 (1.01, 1.59) | 0.041 |
| Household size 10 + | 36: 3.3 (5.4) | 0.60 (0.41, 0.88) | 0.010 | 1.23 (0.78, 1.94) | 0.381 |
| Household size missing | 73: 1.8 (4.0) | 0.33 (0.24, 0.44) | < 0.001 | 0.49 (0.34, 0.69) | < 0.001 |
| No covid-19 | 1009: 5.3 (16.3) | Reference | NA | Reference | NA |
| Previously tested positive more than 2 weeks before survey | 14: 8.2 (10.5) | 1.54 (0.88, 2.69) | 0.130 | 1.30 (0.73, 2.31) | 0.366 |
| Previously suspected to be positive more than 2 weeks before survey | 150: 9.2 (19.0) | 1.72 (1.43, 2.06) | < 0.001 | 1.53 (1.26, 1.85) | < 0.001 |
| Suspected to be positive in last 2 weeks | 55: 5.4 (8.4) | 1.01 (0.75, 1.36) | 0.956 | 1.28 (0.93, 1.76) | 0.129 |
| Tested positive in last 2 weeks | 33: 2.9 (3.3) | 0.55 (0.36, 0.81) | 0.003 | 0.55 (0.33, 0.91) | 0.020 |
| Catered halls | 34: 2.0 (3.3) | 0.32 (0.21, 0.48) | < 0.001 | 0.34 (0.20, 0.56) | < 0.001 |
| Self-catered halls | 228: 4.6 (12.6) | 0.73 (0.62, 0.87) | < 0.001 | 0.68 (0.52, 0.88) | 0.003 |
| Shared house/flat | 613: 6.2 (11.5) | Reference | NA | Reference | NA |
| Live with family | 196: 8.7 (32.1) | 1.41 (1.19, 1.67) | < 0.001 | 1.84 (1.50, 2.25) | < 0.001 |
| Live alone | 96: 2.4 (4.9) | 0.38 (0.30, 0.49) | < 0.001 | 0.74 (0.54, 1.00) | 0.051 |
| Other | 94: 4.4 (7.5) | 0.70 (0.55, 0.89) | 0.004 | 1.06 (0.80, 1.39) | 0.698 |