Normative Data for the New Test of Odour Pleasantness in Healthy Participants

Objective: Olfactory test of odor pleasantness may prove to be additions to comprehensive chemosensory test batteries used in clinical settings. The goal of our work was to establish normative data of the New Test of Odor Pleasantness (NTOP). Methods: A total of 236 healthy participants aged 16 to 93 years were included in the study. NTOP is based on classification of 29 odorants and three chemicals with trigeminal component. The participants were asked to categorize the hedonic tone of the odorant into four classes: pleasant, neutral, unpleasant, and fetid (very unpleasant). The normative data were determined based on results of persons of 16 to 35 years old. The NTOP was compared with two standard tests - Odourized Markers Test (OMT) and Sniffin' Sticks (identification). Results: Median of the NTOP was of 20 in group of age 16-35 years, 19.5 in group of age 36-55 years and 17 in group of > 56. Tenth percentile of the age group 16-35 was 16 points, which is considered as lowest normal points scored. The median numbers of points decreases with age. There is statistically significant decrease in the olfactory capability with increasing age (> 56 years old). Conclusion: NTOP has a similar characteristics as the standard tests of subjective (psychophysical) olfactometry. At the same time the test give us information different from other olfactory tests. The goal of study was to determine the normal value the NTOP of healthy persons in Czech population.