A practical test for retronasal odor identification based on aromatized tablets

Abstract

BackgroundOlfactory perceptions elicited by odors originating from within the body (retronasal olfaction) play a crucial role in well-being and are often disrupted in various medical conditions. However, the assessment of retronasal olfaction in research and the clinical practice is impeded by the lack of commercially available tests and limited standardization of existing testing materials. New MethodThe novel ThreeT retronasal odor identification test employs 20 flavored tablets that deliver a standardized amount of odorous stimuli. The items represent common food- and non-food-related odors. ResultsThe ThreeT test effectively distinguishes patients with olfactory dysfunction from healthy controls, achieving a specificity of 86% and sensitivity of 73%. Its scores remain stable for up to 3 months (r=.79). Comparison with existing methodThreeT test exhibits a strong correlation with “Tasteless powders” measure of retronasal olfaction (r=.78) and classifies people into healthy and patient groups with similar accuracy. Test-retest stability of ThreeT is slightly higher than the stability of “Tasteless powders” (r=.79 vs r=.74). ConclusionsThreeT is suitable for integration into scientific research and clinical practice to monitor retronasal odor identification abilities.