Interindividual differences in acuity for odor and aroma.

To determine the olfactory acuity of 27 subjects a sensory test was presented which was divided into 4 subtests, 2 for nasal and 2 for oral stimulation. Each subtest contained 28 (4 substances X 7 concentrations) olfactory detection tasks (items). The substances used were lemon and rum aroma as well as ethyl butyrate and amyl acetate, the solvents tap water and sugared tap water. Analysis showed that the test provided a clear differentiation between subjects of low, medium, and high olfactory acuity. The intercorrelations among the test substances and the split-half reliabilities of the subtests proved relatively high, whereas only moderate to low intercorrelations among the subtests were found. This was considered an effect of intraindividual variations of olfactory sensitivity. Finally, some conclusions for the construction of acuity tests for odor and aroma are presented.