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

Abstract 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.