Barcelona Olfactory Test - 8: validation of a new test on Spanish population during COVID-19 pandemic

Abstract

In daily clinical practice, most smell tests are difficult to implement due to their long duration. The aim of the present study was to develop and validate a short, easy to perform, and reusable smell test to be implemented during COVID-19 pandemic.120 healthy adults and 195 patients with self-reported olfactory dysfunction (OD) were included. Barcelona Olfactory Test (BOT-8) was used for detection, memory/recognition, and forced-choice identification. In addition, rose threshold test and VAS was performed. The Smell Diskettes Olfaction test (SDOT) was used for correlation in healthy volunteers, and UPSITTM for patients with OD to stablish an anosmia and hyposmia cut-off point. Considering COVID-19 pandemic disposable cotton swabs with odorants were compared with the original test.In healthy population, BOT-8 mean scores for detection was 100%, memory/recognition was 94.5% (SD=1.07), and identification was 89.6% (SD=0.86). In OD patients was 86% (SD=32.8), 73.2% (SD=37.9) and 77.1% (SD=34.2), respectively. BOT-8 demonstrated good test-retest reliability with a 96.7% of observed agreement and a quadratic kappa of 0.84 (p<0.001). Strong correlation was observed for BOT-8 with SDOT (r=0.67, p<0.001) and UPSITTM (r=0.86, p<0.001). Disposable cotton swabs showed an excellent agreement with a kappa of 0.79 compared to the original test. The cut-off point for anosmia was ? 3 (AUC=0.83, Se= 0.673, Sp=0.993).BOT-8 offers an efficient and fast method to be used in clinical routine to assess the smell threshold, detection, memory, and identification. Disposable cotton swabs with odorants are a useful and safe method during the COVID-19 pandemic.