Usefulness of the self-administered odour questionnaire for patients with olfactory dysfunction

Background: The self-administered odour questionnaire (SAOQ), consisting of 20 odours familiar to Japanese people, is proposed as a scoring system for the quantitative evaluation of sense of smell. We examined the correlations between the SAOQ and the standard olfactory test covered by insurance in Japan and evaluated the usefulness of the SAOQ in patients with olfactory dysfunction (OD). Methodology: Data from 3048 patients undergoing treatment for OD between June 2005 and September 2021 were retrospectively analysed. The causative diseases of OD were identified. Correlations between the SAOQ score and olfactory detection and recognition thresholds (DT and RT) were investigated using olfaction tests. The characteristics of each itemised odour of the SAOQ for each causative disease were analysed. Results: Causative diseases of OD were: chronic rhinosinusitis (43%), post-viral (25%), post-traumatic (6%), central nervous system dysfunction (2%), peripheral nervous system dysfunction (2%), congenital (1%), psychogenic (1%), or idiopathic (20%). The SAOQ score correlated with DT and RT in both the pre- and post-treatment stages. The median SAOQ scores significantly declined with RT severity. Analysis of the itemised odour scores of the SAOQ showed that ‘strawberry’ was the most declined-odour, while ‘perfume’ was the most preserved-odour. Conclusions: The SAOQ is a useful scoring interview system for evaluating sense of smell.