The relationship between individual significance of olfaction and measured olfactory function

The subjective importance of olfaction varies greatly across individuals, yet the cause of this variation – such as its relationship to general olfactory function – remains poorly understood. The purpose of this descriptive correlational study was to examine if any relationship exists between subjectively reported significance of olfactory experience and more objective, psychophysical olfactory testing. Specifically, we related the Importance of Olfaction questionnaire (IO-Q), the threshold-discrimination-identification test (TDI) and both their subscales in Bayesian correlation analyses using R and JASP in a sample of 227 neurotypical, young participants from Denmark. The mean age was 27.71 (∼57% females). 176 participants fully completed all tests. We found that the total IO-Q score was weakly positively correlated to the total TDI score (r = 0.141, 95% CI = [-0.007;0.281]). The total TDI score was also weakly positively correlated to the aggravation subscale of the IO-Q (r = 0.117, 95% CI = [0.021; 0.210]), but less so to other subscales. This indicates that greater subjective olfactory importance is only weakly associated with greater measured olfactory function. As such, olfactory test scores may not provide the full picture of olfactory function.