Usefulness of curry odorant of odor stick identification test for Japanese in olfactory impairment screening.

Conclusion: The curry odorant of the odor stick identification test for Japanese (OSIT-J) is useful in screening for olfactory impairment in Japanese subjects.

Objective: The present study was designed to determine the most useful odorant of the OSIT-J in screening for olfactory impairment in Japanese subjects.

Subjects and methods: We studied olfactory impairment screening with the OSIT-J in 83 participants (49 male, 34 female; average age 50 years) in an executive check-up at NTT West Kanazawa Hospital. Olfactory discrimination acuity was evaluated with three odorants of the OSIT-J (rose, curry, and sweaty-smelling clothes), each known to be significantly correlated with the assessment of the Japanese standard olfaction test (T&T olfactometer). Those participants who did not score full marks in tests with the three odors were assessed with another nine odorants of the OSIT-J.

Results: The positive predictive value was 100% in the screening with the curry odorant. In 38 participants who did not identify all three odors correctly, the identification of the curry odor was significantly correlated with the scores for all 12 odors (p<0.005). Identification of the curry odor was not significantly correlated with identification of the menthol odor of OSIT-J.