Hearing Aid Benefits for Age-Related Hearing Loss

Hearing aids provide moderate-to-large benefits on self-reported hearing outcomes compared to no intervention, according to a major systematic review and meta-analysis of 33 randomized controlled trials. The study, led by researchers from the University of Colorado School of Medicine and the University of Pretoria, analyzed data from 4,471 adults with mild-to-severe hearing loss to evaluate the measurable effects of various hearing devices. While hearing aids were shown to be effective, the research also reveals significant gaps in how outcomes are measured and a pressing need for more diverse clinical trials.

## Methodology: A Focus on Randomized Controlled Evidence

The research team, including Pandey, Kruger, and Manchaiah, followed strict Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. They searched three major databases—PubMed, CINAHL, and Embase—for randomized controlled trials (RCTs) involving adults with mild-to-severe hearing loss. To be included, studies had to compare an air-conduction hearing device (like a hearing aid, PSAP, or smartphone hearing aid app) against either a passive control (like a waitlist) or an active control (like a placebo device).

From an initial pool of studies, 33 RCTs met the criteria. The team then calculated effect sizes using Hedges’s *g*, a statistical measure that shows the magnitude of a treatment’s effect. A *g* of 0.2 is considered small, 0.5 medium, and 0.8 large. They used random-effects models to estimate pooled effects, acknowledging the variability between different studies. A major challenge was that many trials did not report data in a way that allowed for meta-analysis, meaning pooled estimates could only be generated for some comparisons.

## Primary Findings: Hearing Aids Lead, But Data Has Limits

The analysis produced several clear, though qualified, results. Compared to no intervention or a waitlist control, hearing aids demonstrated moderate-to-large benefits on hearing-related self-report outcomes, such as questionnaires about hearing handicap or communication difficulty. However, the researchers could not generate a single pooled meta-analytic estimate for this common comparison because too few studies reported usable data.

When compared against a placebo device, hearing aids showed a small pooled effect (*g* ≈ 0.37). This result was largely influenced by trials that included participants with Alzheimer’s disease, suggesting the effect might be different in the general hearing loss population.

Personal sound amplification products (PSAPs), which are typically cheaper, over-the-counter devices, showed a medium pooled effect compared to no intervention (*g* ≈ 0.42). The benefits were seen primarily in hearing-specific self-reports and some behavioral listening tests.

The most striking finding came from direct comparisons between different technologies. Based on data from two trials, hearing aids showed a large pooled advantage over other devices, including smartphone hearing aid applications (SHAAs) and extended-wear hearing aids (EWHAs), with an effect size of *g* ≈ 0.88.

## A Narrow Scope of Measurement and High Heterogeneity

A critical insight from the review is what researchers are *not* measuring. The team found that approximately 81% of the outcomes assessed in these trials were self-reported, and about 45% were behavioral (like speech-in-noise tests). There was “very limited assessment” of cognitive or neurophysiological domains. This means we know little about how using a hearing device might affect brain function, memory, or attention over time, areas of high interest for conditions like tinnitus and hyperacusis where central nervous system changes are key. Readers interested in the brain-based aspects of sound sensitivity may find our article on the neurophysiology behind misophonia relevant.

The statistical heterogeneity in the meta-analysis was high (*I² > 80%*), indicating that the study results varied widely. This prevents firm, generalized conclusions from the pooled data. The authors noted no signs of publication bias, meaning the review likely captured all relevant published data, both positive and negative.

Safety data was reassuring but sparse. Only nine of the 33 studies reported on adverse events, and just one of those reported a single device-related incident.

## Practical Implications and Future Research Needs

For clinicians and patients, this review affirms that hearing aids are an effective intervention for improving self-perceived hearing difficulties. It also provides a benchmark for PSAPs, indicating they offer a meaningful, though generally smaller, benefit compared to doing nothing. The clear performance advantage of hearing aids over other device categories in head-to-head tests supports their status as the standard of care for mild-to-severe loss.

The findings also highlight a mismatch between common patient concerns and what is being studied. Many individuals with hearing loss also report cognitive effort, mental fatigue, and conditions like tinnitus and anxiety. The current evidence base, focused overwhelmingly on self-report and basic behavior, does not adequately address these interconnected issues.

The authors’ conclusion is a direct call to action: the field needs “more rigorous, domain-diverse RCTs.” Future trials should incorporate cognitive testing, brain imaging, or other neurophysiological measures to understand the full impact of hearing devices. This is especially important as hearing health moves toward more integrated care models. For instance, research on noninvasive therapies that reset brain networks shows the value of looking beyond the ear.

**Source:** The full systematic review and meta-analysis, “Effects of Hearing Devices for Adults With Mild-to-Severe Hearing Loss,” is available online ahead of print in the *Journal of Speech, Language, and Hearing Research* (DOI: 10.1044/2026_JSLHR-25-00737).