Effects of different medical masks on acoustic and aerodynamic voice assessment during the COVID-19 pandemic

The purpose of the study was to investigate the effect of the surgical masks and N95 masks on the acoustic and aerodynamic parameters of voice assessment during the coronavirus disease 2019 pandemic. The challenge of the study was to enable each inexperienced participant to perform a number of acoustic and aerodynamic voice assessment in a qualified and homogeneous manner without and with medical masks, and to minimize the individual differences. There were 32 healthy participants recruited in the study, including 16 males and 16 females. The acoustic parameters analyzed included fundamental frequency, standard deviation of fundamental frequency (fundamental frequency standard deviation), percentage of jitter (%), percentage of shimmer (%), glottal-to-noise excitation ratio (GNE), and the parameters of irregularity, noise and overall severity. The aerodynamic parameters included s time, z time, s/z ratio and maximum phonation time. When wearing surgical masks, the GNE ratio (P = .043) significantly increased, whereas noise (P = .039) and s time (P = .018) significantly decreased. When wearing N95 masks, the percentage of shimmer (P = .049), s time (P = .037) and s/z ratio (P = .048) significantly decrease. In general, performing voice assessment with a medical mask proved to be reliable for most of the acoustic and aerodynamic parameters. It is worth noting that the shimmer (%), could be slightly impacted when wearing N95 masks. Wearing surgical masks might slightly influence the measurement of noise and higher GNE ratio. The s/z ratio could be affected when wearing N95 masks. The contribution of the study is to explore acoustic and aerodynamic parameters that might be easily affected by wearing masks during the voice assessment, and provide references for clinical evaluation of voice disorders during the pandemic of coronavirus disease 2019.