Objective and Subjective Outcomes in Patients with Hearing Aids: A Cross-Sectional, Comparative, Associational Study

Outcome assessment for hearing aids (HAs) is an essential part of HA fitting and validation. There is no consensus about the best or standard approach for evaluating HA outcomes. And, the relationship between objective and subjective measures is ambiguous. This study aimed to determine the outcomes after HA fitting, explore correlations between subjective benefit and acoustic gain improvement as well as objective audiologic tests, and investigate several variables that may improve patients' perceived benefits.

Eighty adults with bilateral symmetrical hearing loss using HAs for at least 1 month were included in this study. All subjects completed the pure tone average (PTA) threshold and word recognition score (WRS) tests in unaided and aided conditions. We also administered the Chinese version of International Outcome Inventory for Hearing Aids (IOI-HA), to measure participants' subjective benefits. Objective HA benefit (acoustic gain improvement) was defined as the difference in thresholds or scores between aided and unaided conditions indicated with ΔPTA and ΔWRS. Thus, patients' baseline hearing levels were taken into account. Correlations were assessed among objective audiologic tests (PTA and WRS), acoustic gain improvement (ΔPTA and ΔWRS), multiple potential factors, and IOI-HA overall scores.

PTA decreased significantly, but WRS did not increase when aided listening was compared to unaided listening. Negative correlations between PTAs and IOI-HA scores were significant but weak (r = -0.370 and r = -0.393, all p < 0.05). Significant weak positive correlations were found between WRSs and IOI-HA (r = 0.386 and r = 0.309, all p < 0.05). However, there was no correlation among ΔPTA, ΔWRS, and IOI-HA (r = 0.056 and r = -0.086, all p > 0.05). Moreover, 2 nonaudiological factors (age and daily use time) were significantly correlated with IOI-HA (r = -0.269 and r = 0.242, all p < 0.05).

Correlations among objective audiologic tests, acoustic gain, and subjective patient-reported outcomes were weak or absent. Subjective questionnaires and objective tests do not reflect the same hearing capability. Therefore, it is advisable to evaluate both objective and subjective outcomes when analyzing HA benefits on a regular basis and pay equal attention to nonaudiological and audiological factors.