The purpose of this study is to evaluate hearing aid amplification and tinnitus masker
performance, and clinical benefit for adults with hearing loss and tinnitus. The
participants of the study will include approximately 100 adults with bilateral hearing
loss ranging from mild to profound and mild to severe tinnitus as determined by the
Tinnitus Handicap Inventory.
Participants will be fit with hearing aids by a licensed research audiologist. Hearing
aid fittings will be verified using real-ear measurements and performance will be
evaluated by the response accuracy compared to hearing aid prescriptive targets.
Participants will first be fit with only amplification for 3 months. The participants
will wear the hearing aids regularly in the field and return to the research facility at
several intervals to complete measures of hearing aid performance and listening tasks.
At the three-month mark, a tinnitus masker will be turned on through the participant's
hearing aids. The masker will be adjusted to participant preferences for sound quality
and masker output will be captured using real-ear measurements. The participants will
then wear the hearing aids with a tinnitus masker enabled for 3 months and return to the
research facility at several intervals to complete measures of hearing aid performance
and listening perception tasks.
Through this study the following hypotheses will be tested:
The use of well-fit amplification alone improves participants' ability to hear and
improves tinnitus symptoms as compared to unaided conditions.
The use of well-fit amplification in conjunction with an ear-level tinnitus masker
improves participants' ability to hear and improves tinnitus symptoms.
According to the American Speech, Language, and Hearing Association, "fitting and
monitoring the use of tinnitus maskers, hearing aids, or other ear-level sound
generators" are all acceptable management techniques for tinnitus. However, there is not
guidance on the order of management strategies. In the ASHA guidance and peer-reviewed
literature, there is no evidence of patient characteristics that indicate the patient
will benefit from one intervention over another. There is previous research that
indicates well- fit hearing aids providing amplification alone improves tinnitus symptoms
in individuals with hearing loss and tinnitus. Widely accepted tinnitus management
programs -- Tinnitus Retraining Therapy, Progressive Tinnitus Management, and Tinnitus
Activities Treatment-- recommend the use of tinnitus masking devices in addition to
amplification as a component of tinnitus management for individuals with hearing loss and
tinnitus . In randomized controlled studies, it has been found that participants with
tinnitus showed equal improvement with tinnitus symptoms when fit with amplification only
and when fit with amplification and sound masker devices when compared to no
intervention. These studies indicate improvement in tinnitus with intervention versus no
intervention. The present study will continue this line of research with participants
wearing hearing aids with amplification alone and hearing aids with amplification and a
tinnitus masker.
For this study, all participants will first be fit with hearing aids providing
amplification only for 3 months and then the tinnitus masker will be enabled in the
hearing aids for the second half of the study. This study design was chosen due to the
inability to blind the participant or researcher from the intervention and because it
mimics many patients' experiences with clinical protocols. The study design also reduces
the potential ethical concern of providing the tinnitus masker and removing it as the
researchers may be withholding an effective tinnitus management tool after the
participant has already grown accustomed to it. When the tinnitus masker is enabled at
the 3-month mark, the participants will continue to have access to an amplification only
program they can navigate to with their hearing aids. The participants will be encouraged
to remain in the tinnitus masker program as much as possible.
The study hypotheses will be tested by comparing clinical benefit questionnaires against
normative data or quantifying minimal clinically important differences from unaided to
aided conditions for individual participants. Performance of amplification and tinnitus
maskers will be verified using real-ear measurements and will confirm the safety of the
hearing aids and tinnitus maskers by following the participants for 6 months.
