The AMA method of estimation of hearing disability: a validation study

Area of Science:

• Audiology
• Hearing Science
• Disability Assessment

Background:

• The 1979 American Medical Association (AMA) method is a standard for estimating hearing disability.
• Its underlying assumptions require validation against current audiological practices and patient self-assessments.

Purpose of the Study:

• To rigorously test the assumptions of the 1979 AMA method for hearing disability estimation.
• To compare the AMA method's predictions with self-assessed hearing disability using objective audiological measures.

Main Methods:

• Conventional audiometric testing and the Communication Profile for the Hearing Impaired (CPHI) were administered to 1001 patients.
• A Communication Performance (CP) score from the CPHI served as the gold standard for self-assessed hearing disability.
• Pure-tone thresholds (PTAs) and word recognition scores (WRSs) were correlated with CP scores via multiple regression analysis.

Main Results:

• Better-ear pure-tone averages (PTAs) correlated well with self-assessed hearing disability, with no significant improvement over the 0.5, 1, 2, and 3 kHz PTA used in the AMA method.
• The AMA's better-ear weighting of 5:1 and its assumptions of no disability below 25 dB HL and linear growth were supported.
• Combining PTAs and WRSs yielded only marginal improvements in predicting hearing disability.

Conclusions:

• The findings support the continued use of the 1979 AMA method for estimating hearing disability.
• Incorporating word recognition scores (WRSs) into disability estimation methods is not recommended due to negligible accuracy gains and potential for exaggeration in legal contexts.