Re: Face masks for the public during the covid-19 crisis: More caution
Dear Editor,
It is necessary to add more caution to the application of the precautionary principle in the case of face masks (1).
This principle should be applied to all proposed interventions systematically, as principles of evidence based medicine teach us.
Example: Major of Moscow ordered Moscow citizens to wear not only face masks in public places, but also the gloves. Being systematic, one should apply the precautionary principle to the recommendation to wear gloves.
Any intervention has its costs. One of the costs is that once accepted on the base of the insufficient evidence they may harm directly or indirectly (2). The costs of the face masks is not dangerous, but other dangers are possible.
In general the systematic use of the precautionary principle may involve enormous costs and harms more than the harm from the real or imagined problem they are designed to prevent (3).
1. Greenhalgh T, Schmid MB, Cypiononka t, et al. Face masks for the public during the COVID-19 crisis. BMJ 2020;369:m1435 doi: 10.1136/bmj.m1435
2. Ioannidis, J. P. A. (2020). "Coronavirus disease 2019: The harms of exaggerated information and non-evidence-based measures." Eur J Clin Invest 50(4): e13222. doi: 10.1111/eci.13222
Vlassov, V. V. (2017). "Precautionary bias." Eur J Public Health 27(3): 389-389. doi: 10.1093/eurpub/ckx013
Rapid Response:
Re: Face masks for the public during the covid-19 crisis: More caution
Dear Editor,
It is necessary to add more caution to the application of the precautionary principle in the case of face masks (1).
This principle should be applied to all proposed interventions systematically, as principles of evidence based medicine teach us.
Example: Major of Moscow ordered Moscow citizens to wear not only face masks in public places, but also the gloves. Being systematic, one should apply the precautionary principle to the recommendation to wear gloves.
Any intervention has its costs. One of the costs is that once accepted on the base of the insufficient evidence they may harm directly or indirectly (2). The costs of the face masks is not dangerous, but other dangers are possible.
In general the systematic use of the precautionary principle may involve enormous costs and harms more than the harm from the real or imagined problem they are designed to prevent (3).
1. Greenhalgh T, Schmid MB, Cypiononka t, et al. Face masks for the public during the COVID-19 crisis. BMJ 2020;369:m1435 doi: 10.1136/bmj.m1435
2. Ioannidis, J. P. A. (2020). "Coronavirus disease 2019: The harms of exaggerated information and non-evidence-based measures." Eur J Clin Invest 50(4): e13222. doi: 10.1111/eci.13222
Vlassov, V. V. (2017). "Precautionary bias." Eur J Public Health 27(3): 389-389. doi: 10.1093/eurpub/ckx013
Competing interests: No competing interests