Wearing of face masks does not make people complacent about social distancing

The use of face masks during the COVID-19 pandemic does not reduce compliance to social distancing or other public health control measures, a recent study has found.

Drawing from two naturalistic studies, the researchers looked at video recordings at two Dutch cities. The outcome of interest was whether or not an observed individual was 1.5-m away from the closest person, in accordance with Dutch national guidelines. Analyses were conducted according to whether or not the observed individual was wearing a face mask.

The first study included 60 h of footage with an average window of observation of 25 s. More than half of the observed individuals violated the 1.5-m social distancing mandate, a proportion that dropped to around 10 percent when the inter-person distance was reduced to 0.5 m.

Regression analysis showed no link between mask-wearing and violation of the 1.5-m guideline (β, 0.03, 95 percent confidence interval [CI], –0.04 to 0.09; p=0.398). Instead, crowding emerged as the strongest factor predicting such violations (β, 0.33, 95 percent CI, 0.21–0.46; p<0.001).

These findings were confirmed in the second study, which was designed to replicate the methodology of the first study. Over around 500 h of footage with an average observation time of 23 s, around 70 percent of the observed individuals violated the 1.50-m distancing protocol, while 30 percent passed by within 0.5 m of another person.

As in the first study, regression analysis revealed no link between mask-wearing and social-distancing violations (β, 0.03, 95 percent CI, –0.05 to 0.10; p=0.511), while crowding remained significantly associated (β, 0.18, 95 percent CI, 0.10–0.26; p<0.001).

“It would be a cause for concern if face masks reduced the adherence to social distancing directives, as predicted by the risk-compensation hypothesis,” the researchers said.

“The current study helps alleviate that concern, with internally replicated observational evidence for the absence of a mask-distancing association and natural-experimental data showing that a mask mandate was not associated with social distancing and crowding levels,” they added.