RP309 - Combining Subjective Ratings and a Digit Triplet Test to Identify Potential Hearing Aid Users

Abstract: The purpose of this study was to evaluate two screening methodologies (subjective ratings and digit triplet test) for identifying hearing aid users. Adults (n = 157) provided details about hearing aid use and completed two screening tests, a single perceived hearing ability rating and a digit triplet test. The digit triplet test as a screening tool provides better specificity (correctly identifying non-users) than a subjective rating alone, but the sensitivity was lower (missing hearing aid users). The combination of subjective ratings and digit triplet test could be useful for correctly identifying adults who are likely to use hearing aids.

Summary: Rationale: Not all adults who could benefit from hearing aids use them. One of the ways to expand hearing aid adoptions could be to improve hearing aid accessibility by reaching a larger pool of hearing aid candidates outside of traditional dispensing clinics. For example, screening tools available online or in primary care physicians’ offices could be used to refer patients who are likely to adopt hearing aids to dispensing professionals for further evaluation and potential hearing aid selection. The factors that have been shown to influence hearing aid adoptions are multifaceted, including complex considerations like insurance coverage, social support, identity, and self-efficacy. The optimal screening tool would be simple, sensitive, and specific. The purpose of this study was to evaluate two screening methodologies (subjective ratings and digit triplet test) for identifying hearing aid users.

Design: In addition to completing two screening tests, adults (n = 157) aged 40 to 82 years (mean = 65.7) completed air- and bone-conduction testing and provided details about hearing aid and hearing health history. The two screening tools were: 1) a single question about their perceived hearing ability (scale of 1 to 10) and 2) digit triplet test where the signal-to-noise ratio is varied to determine the SNR at which a participant could identify three digits. Sensitivity and specificity analyses were conducted to evaluate the ability of each screening tool for predicting hearing aid use and for predicting audiometric hearing loss (defined as pure-tone average of 500, 1000, 2000, and 4000 Hz greater than 15 dB HL).


Results: Both screening tools were more sensitive and specific when predicting hearing aid use than predicting audiometric hearing loss. For predicting hearing aid use, subjective ratings of hearing ability had a sensitivity of 85% and a specificity of 77%. Adults with rated hearing abilities of 6.5 or worse were more likely to be hearing aid users than those with ratings higher (better) than 6.5. The digit triplet test (using the better ear threshold) had a sensitivity of 61% and specificity of 93%. Follow-up analysis exploring the subjective hearing ability ratings revealed that those who were incorrectly identified as non-users with the digit triplet screening had low subjective ratings of hearing ability (mean = 5.2).

Conclusions: The digit triplet test as a screening tool provides better specificity (correctly identifying non-users) than a subjective rating alone, but the sensitivity is lower (missing hearing aid users). However, the subjective ratings of participants who ‘passed’ the digit triplet screening could be used to correctly identify hearing aid users. The combination of subjective ratings of hearing difficulty and digit triplet test could be a useful screening tool to identify adults who are likely to use hearing aids and could be used to generate referrals when implemented in non-audiology clinics. Future research is warranted to identify the utility of the screening tool for improving hearing aid adoption rates when implemented in various serve delivery models.

Brief Summary of Clinical Takeaways: Combining subjective ratings with a digit triplet test screener is a sensitive and specific method of identifying potential hearing aid users. This could be a useful screening tool to identify adults who are likely to use hearing aids and could be used to generate referrals when implemented in non-audiology clinics.

Assumptions: Attendees should have an understanding of the difference between screening and diagnostic tools and some understanding of current service delivery models for acquiring hearing aids.