The reliability and validity of the comfort level method of setting hearing aid gain

The comfort level method (Carhart, 1946) probably is the most widely used procedure for setting the acoustic gain of hearing aids. A series of experiments were conducted to determine the test-retest reliability of the comfort level method and the relationship between the comfort settings established in a clinical test suite and the comfort settings utilized in more realistic daily listening situations. Adults with bilateral sensorineural hearing impairments were subjects. The results suggest that the comfort level method has good test-retest reliability for most clinical purposes. Further, clinically established comfort settings may accurately represent typical daily-use settings if the input level used to establish the comfort settings in the clinical environment is 70 dB SPL.