Edinburgh Napier University

  Purpose
Although a well-established aspect of healthcare practice, the impact of facemasks on verbal communication is surprisingly ambiguous.

Materials and Methods
A systematic search was conducted in APA PSYCHinfo, CINAHL, NHS Knowledge Network, Medline and SPORTDiscus databases from inception to November 2022 according to the PRISMA guidelines. Studies reporting an objective measure of speech understanding in adults, where information was transmitted or received whilst wearing a facemask were included. Risk of bias of included studies was assessed with the Newcastle-Ottawa score.

Results
Four hundred and thirty-three studies were identified, of which fifteen were suitable for inclusion, incorporating 350 participants with a median age of 49 (range 19 to 74) years. Wide heterogeneity of test parameters and outcome measurement prohibited pooling of data. 93% (14 of 15) studies reported a deleterious effect of facemasks on speech understanding, and 100% (5 of 5) of the included studies reported attenuation of sound with facemask usage. Background noise added further deleterious effects on speech understanding which was particularly problematic within hearing-impaired populations. Risk of bias in included studies varied but overall was modest.

Conclusions
Despite considerable complexity and heterogeneity in outcome measure, 93% (14 of 15) articles suggest respiratory protective equipment negatively affects speech understanding in normal hearing and hearing-impaired adults.

Implications for Rehabilitation
As a result of the covid-19 pandemic, facemask use is now commonplace across all healthcare and rehabilitation settings and has material implications for interpersonal communication.

This systematic review of human communicative studies highlights that the use of facemasks does indeed inhibit communication through effects on speech intelligibility and through sound attenuation.

These effects are evident in both normal hearing and hearing-impaired adults due to the visual cues required with lipreading and facial expressions during communication.

The presence of background noise also produces deleterious effects on speech understanding and is more problematic for hearing-impaired populations.

Simple recommendations to reduce background noise (where possible), to step closer (where social-distancing rules permit), to speak louder or to use speech to text applications (if practical) could all mitigate these communicative barriers. Further an awareness of persons with hearing impairments, the function (or otherwise) of hearing aids in those patients that require these, and an ability to use transparent facemasks can be specifically helpful.