Comparison of the Hearing Benefits and User Satisfaction With Hearing Aids and Personal Sound Amplification Products: A Multicenter Prospective Randomized Crossover Trial

Abstract

Background

While hearing aids (HAs) remain the primary intervention for hearing loss, their high cost creates barriers to access. Personal sound amplification products (PSAPs) are a more affordable alternative, but few studies have compared their efficacy to those of HAs. This multicenter, prospective, randomized, crossover trial was conducted to compare audiologic performance and user satisfaction between HAs and PSAPs to evaluate PSAP potential as alternatives for hearing rehabilitation.

Methods

A total of 73 participants with sensorineural hearing loss was enrolled. Participants used one hearing device (HA or PSAP) for 3 months before changing to the other for 3 months. Outcome measures were pure-tone audiometry, word recognition score, and Hearing in Noise Test score. Subjective satisfaction was measured using standardized questionnaires—the Abbreviated Profile of Hearing Aid Benefit and the International Outcome Inventory for Hearing Aids—and two custom surveys.

Results

HAs showed superior performance in high-frequency functional gain, speech perception in noise, and user satisfaction compared to PSAPs. Premium HAs demonstrated better performance than basic HAs, while basic HAs significantly outperformed both high-end and basic PSAPs. No significant differences were found between high-end and basic PSAPs.

Conclusion

The superior audiologic performance of and user satisfaction with HAs compared to PSAPs support their continued preference for hearing rehabilitation. Although PSAPs offer a more affordable option, they may not meet the needs of individuals with hearing loss, particularly in terms of high-frequency gain and speech perception.

Trial Registration

iCreaT Identifier: C220078

Graphical Abstract

INTRODUCTION

Hearing loss is a significant global health concern. More than 5% of the world’s population requires rehabilitation for hearing impairment.1 Hearing aids (HAs) are the primary intervention for hearing impairment due to their well-documented effectiveness.2 However, despite their crucial role in hearing rehabilitation, HA coverage rates remain inadequate worldwide. In low- and middle-income regions, which comprise 85% of the global population, coverage rates range from 1.5% to 12%, while rates in high-income countries are as high as 57%.3

The cost of HAs is consistently identified as the primary barrier to adoption.4,5 To address this financial constraint, several alternatives have emerged, including over-the-counter (OTC) HAs, personal sound amplification products (PSAPs), and smartphone-based HA applications.6,7 Among these, OTC HAs received U.S. Food and Drug Administration (FDA) approval in 2022 for non-prescription sales.8 As of 2024, while prescription HAs typically cost between $2,000 and $8,000 per pair, OTC HAs are substantially more affordable, ranging from $600 to $1,000 per pair.9 However, OTC HA availability varies by country; for instance, they have not yet received approval from the Korean FDA.

Unlike OTC HAs, PSAPs are not classified as medical devices and thus face less stringent regulatory oversight. This regulatory distinction has paradoxically increased interest in PSAPs as potential alternatives to conventional HAs.10 However, PSAPs are not designed for individuals with hearing loss but as “wearable electronic products designed to amplify environmental sounds for individuals who do not have hearing impairment.”11 Despite this regulatory classification, the 2022 MarkeTrak report revealed that 8.2% of individuals with hearing difficulties use PSAPs as their primary hearing device.12 Given the growing global demand for non-medical hearing amplification devices, evaluating the effectiveness of PSAPs for individuals with hearing difficulties has become increasingly important.

This study aimed to compare the speech intelligibility and subjective satisfaction between PSAPs and HAs to determine whether PSAPs are an alternative to HAs for managing hearing loss.

METHODS

Participants

Between May 1, 2022, and July 31, 2024, patients who visited the otolaryngology departments of one of five university hospitals were screened for eligibility. Inclusion criteria were age 18 years or older with a four-frequency average pure-tone audiometry (PTA) threshold ([500 Hz + 1,000 Hz + 2,000 Hz + 4,000 Hz]/4) in the worse ear between 25 and 70 dB due to acquired sensorineural hearing loss. Exclusion criteria were previous use of hearing-assistive devices, inability to participate in tests due to communication difficulties, auditory tract lesions or central nervous system disorders, and potential secondary gains related to clinical trials.

Eligible participants provided written informed consent following consultations at the outpatient clinic. All patient data were managed through the Korea National Institute of Health’s web-based platform, the Internet-based Clinical Research and Trial Management system (iCreaT, https://icreat2.nih.go.kr), under registration number C220078.

Study design

This prospective, randomized, crossover trial involved participants using one assigned device for 3 months before switching to the alternate device for another 3 months. Randomization was conducted using sequentially numbered, opaque, sealed envelopes containing allocation details, generated according to a randomization table prepared by the Department of Preventive Medicine at Seoul National University College of Medicine. Randomization determined HA or PSAP assignment, with specific devices determined by availability at each participating institution. Assessments were performed at three points: baseline, 3 months, and 6 months. Data from 73 participants were analyzed, with participant allocation detailed in Fig. 1.

Fig. 1. CONSORT flow diagram.

PSAP = personal sound amplification product, HA = hearing aid.

Device information

To minimize device-specific bias, various HAs and PSAPs were utilized. HAs were categorized based on channel count. Premium HAs (≥ 10 channels) evaluated were the LiNX 3D (GN ReSound, Ballerup, Denmark) and UNIQUE 330 (Widex, Lynge, Denmark), while basic HAs (< 10 channels) were the UNIQUE 220 (Widex), Enya 4 (GN ReSound), and Enya 3 (GN ReSound). PSAPs were classified by price and channel count: the high-end PSAP was the SmartEar (Olive; $253/ear) with 16 channels, while the basic PSAP was the EM-C110 (BeethoSoL; $210/pair) with five channels. Both PSAP types featured noise reduction, feedback cancellation, and self-fitting capabilities.

HAs were fitted by audiologists using manufacturer-specific software—Widex Compass GPS for Widex devices and ReSound Smart Fit for GN ReSound devices. In contrast, PSAPs were manually adjusted by participants themselves for volume and auditory clarity according to their preferences, reflecting their design for user-driven adjustment without specialist involvement in real-world settings.

Outcome measures

Hearing abilities were assessed at three visits using audiologic assessment and self-report questionnaires. PTA thresholds and word recognition score (WRS) were measured under unaided and aided conditions. WRS was evaluated using the Korean Standard Monosyllabic Word Lists for Adults at 50 dB HL in a sound field, with masking applied to the contralateral better ear.13 Functional gain was calculated as the difference between unaided and aided thresholds. Speech perception in noise was assessed using the Korean version of the Hearing in Noise Test (HINT, HINT pro 7.2; Bio-logic® Systems, Natus Medical Inc., Pleasanton, CA, USA), with background noise (BN) at 65 dB delivered through a loudspeaker at 0° azimuth and 1 meter distance. The signal-to-noise ratio (SNR) for 50% correct sentence identification was recorded.14

Subjective satisfaction was evaluated using two validated questionnaires and two custom surveys. The Korean version of the Abbreviated Profile of Hearing Aid Benefit (APHAB) assesses hearing difficulties through 24 questions across four subscales: ease of communication (EC), reverberation (RV), BN, and aversiveness (AV), using a 7-point Likert scale.15 The Korean version of the International Outcome Inventory for Hearing Aids (IOI-HA) evaluates overall satisfaction through seven questions on a 5-point Likert scale.16 The Korean version of the APHAB was used with permission. © 1991, 1993, 1996, The University of Memphis. All rights reserved.

Additionally, two customized satisfaction surveys were developed for this study. The first survey assessed items of 1) overall satisfaction, 2) hearing improvement, 3) cosmetic appearance, and 4) cost-effectiveness. The second survey comprised 16 items. The first question asked, “Would you recommend hearing assistance devices to neighbors or family members with hearing difficulties?” with three response options: “yes,” “no,” and “don’t know.” The remaining 15 questions evaluated specific aspects of device performance, including 2) ease of battery replacement, 3) battery life, 4) clarity and tone of sound, 5) presence of whistling or beeping sounds, 6) ease of volume adjustment, 7) reliability, 8) maintenance cost, 9) naturalness of sound, 10) sound directionality, 11) cleaning frequency, 12) packaging and accessories, 13) perception of one’s own voice, 14) wind noise, 15) sounds associated with chewing or swallowing, and 16) richness and clarity of sound.

Statistical analysis

Test results were summarized using descriptive statistics, including means and standard deviations. Data were assessed for normality, and appropriate statistical tests were applied. For paired comparisons between two groups, the paired t-test or Wilcoxon signed-rank test was employed depending on the data distribution. For comparisons among independent groups, one-way analysis of variance (ANOVA) or the Kruskal-Wallis test was applied. Comparisons among three paired groups were performed using repeated measures ANOVA or the Friedman test, followed by post-hoc Wilcoxon signed-rank tests. The Bonferroni method was applied for multiple comparisons. Participants with more than 20% missing values were excluded from the analysis, and multiple imputation was used for all participants with less than 20% missing data. All analyses were conducted based on the intention-to-treat principle. Statistical analyses were performed using SPSS software version 24 (IBM Corp., Armonk, NY, USA), with statistical significance set at P < 0.05.

Ethics statement

This study was conducted in accordance with the principles outlined in the Declaration of Helsinki for biomedical research involving human participants. The study protocol received approval from the Institutional Review Boards of all participating hospitals: Seoul St. Mary’s Hospital (KC20OISI0663), Chungnam National University Hospital (2020-11-003), Korea University Hospital (2020GR0020), Samsung Medical Center (2020-08-087), and Seoul National University Hospital (2003-028-1109). All subjects provided written informed consent prior to participation in this study.

RESULTS

Clinical characteristics of enrolled participants

Of 120 screened participants, 117 were randomized to the PSAP-first (n = 59) or HA-first group (n = 58). After the initial 3-month period, 30 participants withdrew from the study (PSAP: 19, HA: 11); following device change, 14 additional participants withdrew (PSAP: 11, HA: 3). Overall dropout rates were 28.3% for PSAP and 14.3% for HA use. Twenty-seven participants used devices unilaterally (right 9 and left 18), with the remainder using bilateral devices.

A flowchart of participant inclusion is presented in Fig. 1, and detailed demographic data are provided in Table 1.

Table 1. Demographic data of analysed participants (N = 73).

Category		Total	Premium PSAP	Basic PSAP	Premium HA	Basic HA	P value
Age, yr		58.1 ± 13.5	56.3 ± 14.2	61.1 ± 12.0	57.8 ± 13.5	58.4 ± 13.7
Sex
	Male	38	25	13	15	23
	Female	35	20	15	13	22
Pure-tone audiometry, dB
	Right	37.7 ± 16.6	36.2 ± 14.6	40.4 ± 19.8	37.8 ± 16.9	37.6 ± 16.7	0.789
	Left	42.5 ± 14.0	42.7 ± 11.9	42.1 ± 17.5	42.7 ± 14.5	42.3 ± 13.9	0.998
WRS, %
	Right	84.6 ± 14.2	85.2 ± 13.5	83.4 ± 15.7	87.2 ± 12.1	82.7 ± 15.4	0.724
	Left	79.0 ± 17.3	79.8 ± 15.1	77.3 ± 21.2	79.4 ± 17.1	78.6 ± 17.7	0.995

Values are presented as mean ± standard deviation

PSAP = personal sound amplification product, HA = hearing aid, WRS = word recognition score.

Audiology test results

Sound field testing showed both PSAPs and HAs to significantly improve hearing thresholds from 250 Hz to 3,000 Hz (all P < 0.05). At 4,000 and 6,000 Hz, only HAs showed significant improvements (P < 0.001). Premium HAs demonstrated superior performance to both PSAP types at higher frequencies (2,000–6,000 Hz, P < 0.05), while basic HAs outperformed PSAPs at select frequencies (Fig. 2A).

Fig. 2. Audiological test outcomes. (A) Sound field test revealed that both PSAPs and HAs significantly improved thresholds in the frequency range of 250–3,000 Hz. At higher frequencies (4,000 and 6,000 Hz), only HAs showed significant threshold improvements. Notably, premium HAs demonstrated the lowest sound field thresholds at high frequencies. (B) HAs exhibited significantly greater functional gain at 250, 500, 2,000, 3,000, 4,000, and 6,000 Hz. Premium HAs showed the greatest functional gain across all frequencies, while basic HAs showed greater functional gain than both high-end and basic PSAPs only in the high-frequency range. (C) WRSs were significantly higher among HA users than both unaided conditions and PSAP users. There were no significant differences between high-end and basic PSAPs or between premium and basic HAs. (D) Speech perception in noise, measured using Hearing in Noise Test with frontal noise, revealed significantly better performance (lower SNR thresholds) with HAs than both unaided conditions and PSAPs. Similarly, no significant differences were observed between high-end and basic PSAPs or between premium and basic HAs.

PSAP = personal sound amplification product, HA = hearing aid, WRS = word recognition score, SNR = signal-to-noise ratio.

^*P < 0.05, ^***P < 0.001.

Functional gain analysis revealed that HAs provided significantly greater benefits at frequencies of 250, 500, 2,000, 3,000, 4,000, and 6,000 Hz (all P < 0.05). Significant differences were observed across all frequencies among the four groups (all P < 0.05). Premium HAs showed significantly higher gain than PSAPs at multiple frequencies, particularly in the higher range (Fig. 2B).

Speech recognition (WRS) improved significantly only with HAs (unaided: 53.0 ± 34.1%, PSAP: 71.6 ± 16.3%, HA: 79.4 ± 14.9%; P < 0.001 for HA). Both premium and basic HAs demonstrated significantly better performance than either PSAP type (P < 0.05) (Fig. 2C).

Speech perception in noise, assessed using HINT with frontal noise, improved with both devices but was superior with HAs (unaided: 10.0 ± 4.0 dB, PSAP: −13.9 ± 4.3 dB, HA: −19.8 ± 4.3 dB; P < 0.001). Both premium and basic HAs significantly outperformed both high-end and basic PSAPs (P < 0.05) (Fig. 2D).

Detailed audiology test results are presented in Supplementary Table 1.

Questionnaire results

Analysis of APHAB questionnaire results revealed no significant differences between the unaided conditions and PSAP use across EC, RV, and BN subscales (all P > 0.05). HA users had significantly lower RV and BN scores than both the unaided and PSAP conditions (P = 0.005 and P < 0.001, respectively), while no significant differences were observed in the EC subscale (P > 0.05). For the AV subscale, PSAP and HA users scored similarly (P > 0.99) but significantly higher than the unaided condition (P = 0.008 and P = 0.040, respectively). In subgroup comparisons, high-end PSAP users had significantly higher scores than premium HA users for the EC (P = 0.001), RV (P = 0.019), and BN subscales (P = 0.003). Basic PSAP users also had significantly higher RV scores than premium HA users (P = 0.040) (Fig. 3A).

Fig. 3. Questionnaire results. (A) HA users demonstrated significantly greater improvement in the EC, RV, and BN categories of the APHAB than the other groups (all P < 0.05). Both PSAP and HA users showed negative responses in the AV category (all P < 0.05). Premium HA users exhibited lower APHAB scores across all categories except AV. (B) HA users reported significantly higher satisfaction across all IOI-HA questionnaire items (all P < 0.01). No significant differences were found between high-end and basic PSAPs or between premium and basic HAs (all P > 0.05).

HA = hearing aid, EC = ease of communication, RV = reverberation, BN = background noise, APHAB = Abbreviated Profile of Hearing Aid Benefit, PSAP = personal sound amplification product, AV = aversiveness, IOI-HA = International Outcome Inventory for Hearing Aids, Ben = benefit, RAL = residual activity limitation, Sat = satisfaction, RPR = residual participation restriction, Ioth = impact on others, QoL = quality of life.

^*P < 0.05, ^**P < 0.01, ^***P < 0.001.

IOI-HA questionnaire results indicated significantly higher scores across all items for HA users than PSAP users (all P < 0.01). Subgroup analysis revealed no significant differences between high-end and basic PSAPs or between premium and basic HAs (Fig. 3B).

Detailed questionnaire results are presented in Supplementary Table 2.

Subjective satisfaction

All participants completed two satisfaction surveys designed by the authors. In the first survey, HA users reported significantly higher satisfaction scores than PSAP users for overall satisfaction (question 1), hearing improvement (question 2), cosmetic appearance (question 3), cost-effectiveness (question 4), and overall average score (all P < 0.001). In subgroup analysis, no significant differences were found between high-end and basic PSAPs, while premium HA users showed significantly higher satisfaction than basic HA users in questions 1 and 2 (P = 0.035 and P = 0.012, respectively).

The second survey comprised 16 questions. For the first question, “Would you recommend hearing assistive devices to neighbors or family members with hearing difficulties?,” participants chose from three options: “yes,” “no,” or “don’t know.” Among PSAP users, 19 (26.0%) responded “yes,” 26 (35.6%) “no,” and 28 (38.4%) “don’t know.” By contrast, among HA users, 56 (76.7%) answered “yes,” 7 (9.6%) “no,” and 10 (13.7%) “don’t know,” indicating significantly higher satisfaction among HA users (P < 0.001). Comparison across the four groups showed that responses from both premium and basic HA users were significantly more positive than those from high-end PSAP users (all P < 0.001) (Fig. 4B).

Fig. 4. Subjective satisfaction survey analysis. (A) The first satisfaction survey revealed significantly higher scores for overall satisfaction, hearing improvement, cosmetic appearance, and cost-effectiveness for HA users than PSAP users (all P < 0.001). While no significant differences emerged between high-end and basic PSAPs, premium HA users demonstrated significantly higher satisfaction than basic HA users in overall satisfaction and hearing improvement (P = 0.035 and P = 0.012, respectively). (B) Responses to the first question of the second survey (“Would you recommend hearing assistive devices to neighbors or family members with hearing difficulties?”) indicated that HA users were significantly more likely to recommend their devices than PSAP users (P < 0.001). High-end PSAPs showed no advantage over basic PSAPs in this aspect. (C) Questions 2–16 of the second survey revealed significantly higher satisfaction among HA users across most device-related aspects, except for ease of battery replacement, battery life, and maintenance costs (all P < 0.05). Subgroup analysis showed significantly higher satisfaction for nine questions (all P < 0.05) in premium HA users.

HA = hearing aid, PSAP = personal sound amplification product.

^*P < 0.05, ^**P < 0.01, ^***P < 0.001.

For the remaining 15 questions evaluating satisfaction with various device-related aspects, HA users reported significantly higher satisfaction (lower scores) than PSAP users, except for battery life (question 3, P = 0.416) and maintenance cost (question 8, P = 0.338) (all other P < 0.05) (Fig. 4C). Subgroup analysis showed no significant differences between high-end and basic PSAPs. However, premium HA users reported significantly higher satisfaction than basic HA users regarding sound clarity and tone (question 4, P = 0.014) and ease of volume adjustment (question 6, P = 0.002).

Detailed subjective satisfaction survey results are presented in Supplementary Table 3.

DISCUSSION

In this study, we compared audiologic performance and subjective satisfaction between HAs and PSAPs. HAs demonstrated superior performance in high-frequency functional gain, resulting in better speech perception in both quiet and noisy conditions. Both validated questionnaires (APHAB and IOI-HA) showed higher subjective satisfaction among HA users than PSAP users across all subscales. Two additional satisfaction surveys also indicated higher overall satisfaction with HAs, except for battery-related issues and maintenance costs. Notably, 76.7% of participants would recommend HAs to neighbors or family members with hearing difficulties, compared to only 26% for PSAPs. These results were consistent across both premium and basic devices.

Our findings revealed significant limitations in PSAPs’ high-frequency functional gain, consistent with previous studies.17,18 High-frequency hearing is crucial for consonant discrimination,19 which likely explains the poorer speech perception performance observed in WRS and HINT tests. While adequate gain in this frequency range is essential for user satisfaction, achieving sufficient high-frequency gain presents several challenges, including feedback phenomena and discomfort in BN.20 PSAP manufacturers may have encountered these technical limitations and either intentionally designed their devices with limited gain, or users may have reduced the gain settings due to discomfort in noisy environments. These differences represent a limitation of PSAPs where professional intervention is not possible. The lack of high-frequency gain may restrict not only speech perception but also real-world listening contexts such as music appreciation.21 Therefore, for PSAP performance to be comparable to HAs, future research should explore methods for delivering adequate high-frequency gain without compromising user comfort.

The basic HAs in our study featured 6 to 8 channels, while the premium HAs had 10 or more channels. Research has shown that, while 4 to 8 channels can improve speech discrimination, additional channels beyond 8 do not yield significant improvements.22 Although basic HAs showed less functional gain than premium HAs across frequencies (except at 250 Hz), there were no significant differences in WRS and HINT results between basic and premium HAs. Moreover, basic HAs demonstrated superior results with regard to high-frequency gain, WRS, and HINT performance than both high-end and basic PSAPs.

Subjective satisfaction with PSAPs was consistently lower than with HAs across all assessment tools. The higher dropout rate among PSAP users (28.3% vs. 14.3% for HAs) further supports this finding. Responses to the survey question about device recommendations provided clear evidence of significantly lower satisfaction with PSAPs.

Our findings contradict previous studies suggesting comparable performance between HAs and PSAPs. A 2022 systematic review suggested that PSAPs offer benefits similar to conventional HAs.10 However, that review was limited by its small sample size, including only five eligible observational studies with 124 patients. Similarly, a 2024 systematic review concluded that premium PSAPs were effective for adults with mild-to-moderate hearing loss,23 but analyzed only 10 studies, with just three prospective randomized control trials with small participant numbers. Our multicenter prospective randomized crossover trial provides more robust evidence suggesting that PSAP performance remains inferior to that of basic HAs.

While overall subjective satisfaction was highest for premium HAs, overall subjective satisfaction was higher for basic HAs than both high-end and basic PSAPs. Interestingly, no significant differences were found between high-end and basic PSAPs in either audiologic or subjective satisfaction, despite the high-end PSAP featuring 15 channels compared to the five of the basic PSAP. This suggests that factors beyond channel count must be considered when evaluating hearing assistance devices.

HAs received higher scores even in the “cost-effectiveness” assessment, despite their higher cost. Although cost remains a significant barrier to HA adoption,4,5 users likely expect satisfaction proportional to their investment. When these expectations are not met, perceived cost-effectiveness diminishes.24 The second survey showed comparable satisfaction between HAs and PSAPs regarding battery life and maintenance costs, but satisfaction with hearing benefits (questions 4, 5, 9, 10, 13, 14, 15, and 16), convenience (questions 2, 6, 11, and 12), and reliability (question 7) were significantly higher for HAs than PSAPs, suggesting superior performance not only in audiological aspects but also practical usability.

Our study strengths include being the first multicenter prospective randomized crossover trial comparing PSAPs and HAs with a relatively large sample size. Additionally, we minimized bias by including diverse devices and conducting comprehensive evaluations. The three-month adaptation period for each device allowed more accurate assessments.25

However, several limitations should be noted. First, our study cannot represent all commercially available PSAPs and HAs, given the continuous release of new devices, and the inclusion of unilateral HA users may have influenced our results. Second, participants could not be blinded to device type due to visible differences in design, brand, and price, potentially introducing expectation bias in subjective satisfaction assessments. Third, while HAs were professionally fitted, PSAPs were adjusted by users themselves without standardized fitting—though this reflects the intended self-fitting nature of PSAPs. Fourth, because all devices were provided free of charge, participants’ cost-related satisfaction may not fully represent real-world consumer behavior. Finally, the higher dropout rate among PSAP users could have introduced selection bias. Therefore, future research should include double-blind randomized controlled studies encompassing a wider variety of PSAPs and HAs.

This study demonstrated superior audiologic performance of HAs to PSAPs and higher overall subjective user satisfaction. Performance and satisfaction levels were highest for premium HAs, while basic HAs, despite providing less hearing gain in high frequencies than premium HAs, exhibited comparable performance in WRS and HINT. There was no significant difference between high-end PSAPs and basic PSAPs, and both were inferior to basic HAs in terms of audiologic assessment and subjective satisfaction. Therefore, for appropriate auditory rehabilitation in individuals with hearing loss, the use of HAs should be prioritized over that of PSAPs.

SUPPLEMENTARY MATERIALS

Supplementary Table 1

Audiology test results

Supplementary Table 2

Questionnaire results

Supplementary Table 3

Subjective satisfaction survey