Volume 15, Number 2—February 2009
CME ACTIVITY - Research
Face Mask Use and Control of Respiratory Virus Transmission in Households
Table 5
Estimates of hazard ratios for ILI in the study*
Variable | Global effect of mask use |
Effect per mask type |
|||
---|---|---|---|---|---|
Hazard ratio (95% CI) | p value | Hazard ratio (95% CI) | p value | ||
1-d incubation period | |||||
Adherence to use of surgical or P2 mask† | 0.26 (0.09–0.77) | 0.015‡ | |||
Adherence to use of surgical mask† | 0.27 (0.06–1.24) | 0.09 | |||
Adherence to use of P2 mask† | 0.24 (0.05–1.08) | 0.06 | |||
No. adults | 1.07 (0.66–1.71) | 0.80 | 1.06 (0.66–1.71) | 0.80 | |
No. siblings | 0.86 (0.55–1.35) | 0.52 | 0.86 (0.55–1.35) | 0.52 | |
Index patient <5 y of age | 0.88 (0.41–1.89) | 0.75 | 0.88 (0.41–1.89) | 0.74 | |
Frailty§ |
0.005‡ |
0.004‡ |
|||
2-d incubation period | |||||
Adherence to use of surgical or P2 mask† | 0.32 (0.11–0.98) | 0.046‡ | |||
Adherence to use of surgical mask† | 0.18 (0.02–1.38) | 0.099 | |||
Adherence to use of P2 mask† | 0.45 (0.12–1.62) | 0.22 | |||
No. adults | 1.13 (0.71–1.81) | 0.60 | 1.14 (0.71–1.82) | 0.59 | |
No. siblings | 0.80 (0.51–1.27) | 0.34 | 0.80 (0.50–1.27) | 0.34 | |
Index patient <5 y of age | 1.02 (0.46–2.24) | 0.96 | 1.02 (0.47–2.25) | 0.95 | |
Frailty§ | 0.004‡ | 0.004‡ |
*ILI, influenza-like illness; CI, confidence interval.
†Time-dependent variable.
‡p<0.05 significant (indicates that the outcome for 1 person is correlated with the outcome of other persons in the household).
§This term measures if the clustering of subjects in households is relevant to quantify the risk of ILI infection.