Figure 1:

Mean absorbances for the 12 studies within the WAI database as of July 1, 2019. Noted in the legend are the peer-reviewed publications associated with the datasets, the number of individual ears, and the equipment used in the study. When multiple measurements were made on the same ear, the average from those measurements was used in the calculation across subjects for a given study. Some subjects have measurements on both a right and a left ear, and some subjects have measurements from only one ear; this figure includes every ear in the database and does not control for the effect of number of ears from each subject.