Influence of visual information and test paradigm on clinical olfactory test results.

Objective: The goal of this study was to determine if visual information and test paradigms affect clinical olfactory test results.

Methods: Three hundred and ninety-seven Japanese patients with complaints of olfactory dysfunction were administered both a new clinical olfactory test, the Odor Stick Identification Test for Japanese (OSIT-J), and the Japanese benchmark olfactory test, T&T olfactometry. Four different methods were used to administer the OSIT-J combining paradigms using word or picture-word alternatives with the four-plus alternative method based on a top-down strategy or the two-step identification method based on a bottom-up strategy. OSIT-J scores were compared for the different methods, referring to benchmark scores obtained with T&T olfactometry.

Results: OSIT-J scores using picture-word alternatives and the four-plus alternative method showed a stronger correlation with T&T olfactometry test scores than those using word alternatives and the two-step identification method, respectively. The average OSIT-J scores of the four-plus alternative method using picture-word alternatives were significantly higher than those using word alternatives in anosmic and severely hyposmic patients. The time required to administer the OSIT-J using both picture-word alternatives and the four-plus alternative method was the shortest of the four OSIT-J methods.

Conclusions: Visual information and test paradigms may affect clinical olfactory test results. The OSIT-J method using picture-word alternatives and the four-plus alternative method may be the most suitable for clinical practice.