The effect of equating loudness on audibility-based hearing aid selection procedures

Area of Science:

• Audiology
• Hearing Science
• Speech Perception

Background:

• The articulation index (AI) is commonly used to assess speech intelligibility and guide hearing aid fitting.
• Current methods often assume the listening condition with the highest AI is optimal.
• Potential negative consequences of differing hearing aid conditions are frequently overlooked.

Purpose of the Study:

• To investigate the relationship between the articulation index (AI) and loudness perception in different hearing aid conditions.
• To re-evaluate hearing aid selection methods and frequency-gain response modifications when loudness is equated across conditions.

Main Methods:

• Calculated the articulation index (AI) for various simulated hearing aid conditions.
• Assessed loudness perception across these conditions.
• Adjusted hearing aid gain to equalize loudness perception between conditions.

Main Results:

• Higher articulation index (AI) values were often associated with significantly increased loudness.
• Equating loudness across conditions led to different conclusions regarding the effectiveness of various hearing aid selection methods.
• The perceived benefit of specific frequency-gain response modifications changed when loudness was normalized.

Conclusions:

• The assumption that the highest AI always indicates the best listening condition may be flawed.
• Loudness equalization is crucial for a valid comparison of hearing aid selection strategies.
• Rethinking the role of AI and loudness in hearing aid fitting is necessary for optimal patient outcomes.