Results of the World's Fair Hearing Tests

The value and usefulness of such a large collection of records is dependent very directly upon the accuracy of the test. Therefore considerable attention was given to the calibration of the hearing test equipment and to the evaluation of factors which might affect the results of the test. There seems little doubt that the records accurately portray the hearing characteristics of that section of the population taking the tests. One of the principal objectives of the study was to determine the hearing acuity and the prevalence of defective hearing in the United States population. The visitors who tested their hearing were not a representative sample of the population with respect to factors affecting hearing. Consequently a second objective was to determine the relation of hearing to such factors as age, sex, place of residence, economic status, etc. This information is necessary in order to apply the Fair data to the whole population or to specialized groups within the population. It is believed that the two important factors, age and sex, have been satisfactorily evaluated. Information on other factors although less complete, is sufficient to justify many applications of the data. In other applications, it is necessary to make reservations and these are described in the text. DESCRIPTION OF THE TEST The tests were made in sound-insulated rooms arranged to seat seven visitors, each partially screened from the others, as shown in Fig. 1. The test and suitable instructions were recorded on phonograph records and given through a telephone receiver which the visitor held to his ear.