Figure 2.
Meta-analysis of risk ratios for the effect of face mask use with or without hand hygiene on laboratory-confirmed influenza from 7 randomized controlled trials with 4,247 participants. (a) Face mask use alone; (b) face mask and hygiene; and (c) face mask with or without hand hygiene. Pooled estimates were not generated if there was high heterogeneity (I2 ≥ 75%). Squares indicate risk ratio for each of the included studies, horizontal line indicates 95% CIs, dashed vertical line indicates pooled estimation of risk ratio, and diamond indicates pooled estimation of risk ratio. Diamond width corresponds to the 95% CI.