HRs from shared frailty Cox proportional hazards model for household members in masks versus control arms (n=597)*
| CRI HR (95% CI)† | ILI HR (95% CI)† | Laboratory-confirmed viral respiratory infections HR (95% CI)† | |
|---|---|---|---|
| Masks arm (index case) | 0.61 (0.18 to 2.13) | 0.32 (0.03 to 3.13) | 0.97 (0.06 to 15.54) |
| Control arm (index case) | Ref | Ref | Ref |
| Age (household) | 1.03 (1.01 to 1.05) |
*Household members (mask arm 302 and control arm 295).
†Multivariate analysis was performed as there were 10 cases of CRI and age was also significant in the univariate analysis. Multivariate analyses were not performed for ILI and laboratory-confirmed viral respiratory infections due to the low number of cases.
CRI, clinical respiratory illness; ILI, influenza-like illness.