Evaluating Rehabilitation Options for Individuals with Hearing Difficulties and Pure-Tone Hearing Thresholds within Normal Limits
At the end of last year, we reviewed an article by Alicea and Doherty (2017) that examined the motivation for hearing health-care intervention services by individuals with normal audiograms who present with hearing difficulties. Since then, two studies have been published that evaluated intervention approaches for these individuals.
In the first study, Roup, Post, and Lewis (2018) evaluated the use of mild-gain hearing aids by adults (n=17) with essentially normal hearing and self-reported hearing difficulties (as determined via the Hearing Handicap Inventory for Adults [Newman et al, 1990]). The results demonstrated that these subjects obtained statistically significant improvements with the use of amplification, as determined via self-report measures and speech recognition in noise. Despite the statistically significant improvements, only three subjects decided to purchase the hearing aids after the study was over.
In the second study, Saunders et al (2018) compared four different intervention strategies: (1) training of communication strategies (CS), (2) CS plus the use of a personal frequency modulation system (FM), (2) CS plus auditory training, (3) CS, FM, and auditory training. The auditory training was Posit Science’s Brain Fitness Program. Subjects were Veterans who had experienced blast exposure, had hearing thresholds no greater than a mild degree of hearing loss at 500-4000 Hz, and reported difficulties hearing. The primary outcome measures, which were collected on 87 of the 99 study subjects, were a speech-in-noise test (HINT) and a self-report questionnaire (PIADS; Day and Jutai, 1996). The conditions that utilized the FM system resulted in the greatest improvements on the HINT; however, statistically significant differences were not noted between intervention strategies on the PIADS. The authors did note that compliance with AT was poor. Approximately 30 percent of the subjects who had used the FM system expressed interest in pursuing amplification after the study was over.
In summary, these studies suggest that patients with subjective hearing difficulties may benefit from amplification. It is, however, important to note that not all subjects reported benefit or decided to pursue amplification after the study. While both of these studies evaluated auditory processing, neither used the diagnosis of an auditory processing disorder as an inclusion criteria. The American Academy of Audiology (2010) suggests that certain auditory processing deficits might be better suited for certain interventions (e.g., amplification) than others. These new studies highlight the need for additional research in this area to help guide clinicians regarding intervention for patients who present with normal hearing and hearing difficulties. It also further reminds us that when providing intervention services, it is essential that fitting parameters are verified and that patient outcomes are assessed, monitored, and documented.