The digital scent device as a new concept for olfactory assessment.

Abstract

Background: There are major challenges in olfactory measurements in clinical practice; therefore, a handheld digital scent device (DSD; Noar MultiScent 20) was developed as a tablet with an integrated storage system for odors. The DSD is a self-administered, handheld device that controls the duration of odor release to the nasal cavity through a touchscreen digital interface with automatic database generation. In this study we aimed to determine the feasibility of this DSD as an olfactory assessment test. Methods: We recruited 180 participants (age [mean ± standard deviation], 34.58 ± 9.71 years; 114 women and 66 men) to participate in smell tests using both the DSD and the 40-item Smell Identification Test (SIT-40), which contained the same type and order of odors and the same multiple-choice answers. The scores were compared and evaluated for correlation between the tests, and test-retest reliability was calculated. Results: The DSD test scores were higher than the SIT-40 scores (median [interquartile range], 32 [5.0] vs 31 [7.0]; p = 0.005). The completion time was less for the DSD test than for the SIT-40 (12.5 [5.0] vs 16 [6.0] minutes; p < 0.001). The tests were strongly correlated (Spearman rho = 0.74; p < 0.001) and exhibited a high level of agreement (Bland-Altman regression coefficient = 0.672; p = 0.003). The DSD test-retest reliability coefficient was 0.820. Conclusion: The DSD is feasible as an olfactory assessment test. The digitalization of olfactory assessment combined with data science may enable new research perspectives in the field of olfaction.