The May 1 article “Face masks in a pandemic: From 'useless' to 'indispensable'” reports about a general worldwide phenomenon of acceptance. However, three months since the COVID-19 outbreak had started, the face mask debate continues to attract media attention in countries that have yet to require or recommend its use by the public. In Britain, renewed interest on the topic is precipitated by the release of a report by the Royal Society on May 4 that called for nationwide mask usage. Instead of bringing the issue to a close, it has aroused criticisms from some scientists who regarded the report as merely a set of opinions.

While it is understood that the science community has a natural duty to trust only evidence, such a stance must not be brought to the extreme of denying the beneficial effects of masking at the population level. Some quarters of the science community demand more rigorous evidence that can quantify the positive and negative effects of masking and which are carried out in actual real world settings.

The conclusive evidence expected to come out only from a gold standard randomized controlled trial with a “zero mask” control group is almost impossible to implement due to ethical concerns. Similarly, it is difficult to tease out the specific contribution of masking among the repertoire of coronavirus-fighting measures as social distancing and hand sanitation which are recommended altogether.

One should remember that public health is both an art and a science. According to one leading authority in the field, the art dimension is to “deal with complexity and uncertainty, and an evidence base which may not be complete.” Readers may wish to recall that the gap on disagreement about masking is not new, as seen in the April 30, 2009, Japan Times article "Britain, Japan at odds on face mask merit" during a swine flu outbreak. The longevity of the masking debate is unusual and it appears unnecessary. While the supposed primacy of scientific evidence may be discounted, many lives are at stake and isn’t it right to let common sense prevail and gather more evidence later?

Benjamin Chan

Hong Kong

The opinions expressed in this letter to the editor are the writer's own and do not necessarily reflect the policies of The Japan Times.