A Comparative, Controlled, Clinical Investigation and Quality Control of a New Hearing Aid

Speech test scores will be measured with speech reception thresholds (SRTs) of speech in noise in three conditions: unaided, aided with the current device, and aided with the new device. The score is measured by the the signal-to-noise ratio (SNR) at which 50% of words in a sentence list are correctly repeated. The speech is always presented at 65 dB and the background noise varies to maintain the 50% correct. A lower SNR score indicates a better score. The maximum score will be 15 dB and the minimum will be -5 dB.

Time frame: 2 hour period of speech testing during a lab appointment after wearing the devices for approximately 2 weeks.

Events will be measured by the reporting of unexpected sounds or behavior of the device through questionnaires, diaries, and interviews. The number of events reported including AEs related to the device will be used to measure the outcome. Less events is a better outcome.

Time frame: A 2 hour period of interviews and questionnaires after having worn the devices for approximately 2 weeks and keeping a diary to make notes of device behavior.

The usability of the new device will be measured with a 3-point rating scale used by the tester to evaluate tasks performed by the end user as well as questionnaires and interviews. The questionnaire asks subjects to perform tasks, and the clinician rates the ease with which they complete the tasks. 2 is the highest score meaning that they could complete without help, 1 means that they required some assistance, and 0 means that they could not complete the task. A higher score means a better outcome.

Time frame: 2 hour period of usability testing with tasks and questionnaires.

Word recognition test scores will be measured with two signal-to-noise ratio (SNR) levels in percent correct in two conditions, with the new feature on and the new feature off. The test is a speech test with the words stated in noise at either a 5 dB SNR or a 15 dB SNR. The subject is presented with 5 rhyming words and must choose which word they heard. It is a forced choice meaning that the test will not continue with the next word until they've made a selection. They cannot leave any blank and are not penalized for wrong answers. The score is a percentage of words correct with the maximum score being 100% and the minimum being 0%. A higher score means a better outcome.

Time frame: 2 hour period of speech testing during a lab appointment after wearing the devices for approximately 2 weeks.

The subjective performance for the new device will be measured with the APHAB questionnaire (Abbreviated Hearing Aid Benefit Profile). The questionnaire is a list of 24 statement that the subjects must agree or disagree with using a scale of units from A to G (A being Always and G being Never). Each letter has a corresponding score used for the calculation: A receives 99, B receives 87, C receives 75, D receives 50, E receives 25, F recevies 12, and G receives 1. An average for each subscale is calculated, and a global or overall score can be calculated by taking the mean of the three positive subscales (Ease of communication, Background noise, and Reverberation). For these three subscales a higher score indicates a better performance. The highest possible score is 99 and the lowest is 1. The fourth scale (Aversiveness) is a negative scale meaning that a higher score means a worse performance. The highest possible score is 99 and the lowest is 1.

Time frame: A 2 week time period during which they will wear the devices and answer questionnaires about the experience.

Population: For this questionnaire, two participants had left the study and data was not collected.