Clinical Usefulness of Odor Stick Identification Test for Patients with Olfactory Disturbance

The odor stick identification test for Japanese (OSITJ) is the latest in measuring olfactory identification. It consists of 13 odorants familiar to the Japanese population. We studied the relationship between the Japanese standard olfactory test (T & T olfactometer) and the OSITJ in 182 patients with olfactory disturbance. The identification ratio in 2 of OSITJ tests using 13 odorants was correlated significantly negatively with the detection and recognition threshold measured by the T & T olfactometer. A high correlation between identification ratio and olfactory thresholds was maintained even when the number of odorants in the OSITJ was reduced to 2. For each odorant used, the identification ratio correlated significantly with olfactory thresholds. Results from the OSITJ provide a measure of the degree of olfactory deficit because the ratio of correct answers obtained by the OSITJ decreased gradually with of the severity of olfactory disturbance. Compared to the T & T olfactometer, the OSITJ has several advantages for use in the clinic. These include minimal odor pollution of the test room, simplicity of use, and shorter clinical time needed to administer the test. The OSITJ may be ideal for use in screening due to the minimum number of odorants needed. In conclusion, the OSITJ is useful for detecting and evaluating olfactory disturbance in Japanese people.