Evaluating Hearing Aid Service Delivery Models

The purpose of this study is to compare the outcomes for two different hearing-aid delivery models. In one model, the audiologist selects and fits the hearing aid and, in the other model, the consumer does this directly.

The objectives of this study were to determine efficacy of hearing aids in older adults using audiology best practices, to evaluate the efficacy of an alternative over-the-counter (OTC) intervention, and to examine the influence of purchase price on outcomes for both service-delivery models. The design of this study was a single-site, prospective, double-blind placebo-controlled randomized trial with three parallel branches: (a) audiology best practices (AB), (b) consumer decides OTC model (CD), and (c) placebo devices (P). Outcome measures were obtained after a typical 6-week trial period with follow-up 4-week AB-based trial for those initially assigned to CD and P groups. Older adults from the general community were recruited via newspaper and community flyers to participate at a university research clinic. Participants were adults, ages 55-79 years,with mild-to-moderate hearing loss. Intervention(s): All participants received the same highenddigital mini-behind-the-ear hearing aids fitted bilaterally.AB and P groups received best-practice services from audiologists; differing mainly in use of appropriate (AB) or placebo (P) hearing aid settings. CD participants self-selected their own pre-programmed hearing aids via an OTC model. Primary outcome measure was a 66-item self-report, Profile of Hearing Aid Performance/Benefit. Secondary outcome measure was the Connected Speech Test benefit.

All subjects received hearing aids, some selected by audiologist, some selected by consumer, and some programmed as placebo devices.

Change from unaided to aided performance on the Profile of Hearing Aid Performance with the difference in aided and unaided scores labeled Profile of Hearing Aid Benefit (PHAB), a self-report measure of benefit. The aided and unaided PHAP scores are proportions of time difficulties encountered in various listening situations. Low PHAP scores indicate less frequent difficulties. When subtracting aided from unaided PHAP scores, a positive PHAB score reflects less frequent problems when wearing a hearing aid compared to without. The range of possible PHAB scores are -1.0 to +1.0 with 0.0 indicating no difference between aided and unaided performance. There are seven subscales of the PHAP/PHAB and the scores reported are based on the arithmetic means of the five subscales that deal with speech communication, PHABglobal. These include the following subscale scores: EC (Ease of Communication), FT (Familiar Talkers), BN (Background Noise), Reverberation (RV) and Reduced Cues (RC).

A standardized speech-perception test, based on meaningful sentences and keyword scoring, the Connected Speech Test (CST) was administered unaided and aided. Each CST score represents the percentage of keywords (out of 50) repeated correctly following presentation via loudspeakers. Scores can range from 0 to 100% correct with higher scores indicating better speech perception. For the CST benefit scores reported below, unaided CST scores are subtracted from aided scores such that positive values represent better performance for aided than unaided listening. The possible range of CST benefit scores is -100 to +100 with 0 representing no difference between unaided and aided speech-perception performance.

Inclusion Criteria: (for groups 1-4) 55-79 yrs of age Native English speaker no prior hearing aid use ability to read 18 point font Exclusion Criteria: (for groups 1-3) hearing loss too severe or too mild for hearing aid middle-ear conductive pathology present asymmetrical hearing loss presence of dementia, Parkinson's disease, or other neurological disorder Exclusion Criteria : (for groups 1-4) - subject not interested in purchasing hearing aids

Study protocol, study forms, and final publication all available via Open Access publication in the American Journal of Audiology in March, 2017. De-identified individual data available from PI upon request.

Open Access to protocol, study forms, and detailed results via publication in March, 2017. De-identified data available from investigator upon request.

Humes LE, Kinney DL, Main AK, Rogers SE. A Follow-Up Clinical Trial Evaluating the Consumer-Decides Service Delivery Model. Am J Audiol. 2019 Mar 15;28(1):69-84. doi: 10.1044/2018_AJA-18-0082. Erratum In: Am J Audiol. 2019 Sep 13;28(3):730.

Humes LE, Rogers SE, Quigley TM, Main AK, Kinney DL, Herring C. The Effects of Service-Delivery Model and Purchase Price on Hearing-Aid Outcomes in Older Adults: A Randomized Double-Blind Placebo-Controlled Clinical Trial. Am J Audiol. 2017 Mar 1;26(1):53-79. doi: 10.1044/2017_AJA-16-0111. Erratum In: Am J Audiol. 2019 Sep 13;28(3):730.