Table 3.

Multivariable cluster adjusted log binomial model of any co-infections compared with control group.

Variables in the model	Relative risk (95% CI)
N95	0.41 (0.23–0.75)a, †
Medical mask	0.87 (0.44–1.73)
Hospital level	1.41 (0.77–2.56)
High-risk procedure	1.45 (0.84–2.50)
Influenza vaccine	0.90 (0.46–1.78)
Hand washing	1.07 (0.51–1.23)

^aEfficacy 59%.

^†Significant p values (p < 0.01).