Development and evaluation of the British English coordinate response measure speech-in-noise test as an occupational hearing assessment tool.

OBJECTIVE: The studies described in this article outline the design and development of a British English version of the coordinate response measure (CRM) speech-in-noise (SiN) test. Our interest in the CRM is as a SiN test with high face validity for occupational auditory fitness for duty (AFFD) assessment. DESIGN: Study 1 used the method of constant stimuli to measure and adjust the psychometric functions of each target word, producing a speech corpus with equal intelligibility. After ensuring all the target words had similar intelligibility, for Studies 2 and 3, the CRM was presented in an adaptive procedure in stationary speech-spectrum noise to measure speech reception thresholds and evaluate the test-retest reliability of the CRM SiN test. STUDY SAMPLE: Studies 1 (n = 20) and 2 (n = 30) were completed by normal-hearing civilians. Study 3 (n = 22) was completed by hearing impaired military personnel. RESULTS: The results display good test-retest reliability (95% confidence interval (CI) < 2.1 dB) and concurrent validity when compared to the triple-digit test (r ≤ 0.65), and the CRM is sensitive to hearing impairment. CONCLUSION: The British English CRM using stationary speech-spectrum noise is a "ready to use" SiN test, suitable for investigation as an AFFD assessment tool for military personnel.

Fit for the frontline? identification of mission-critical auditory tasks (MCATs) carried out by infantry and combat-support personnel.

The ability to listen to commands in noisy environments and understand acoustic signals, while maintaining situational awareness, is an important skill for military personnel and can be critical for mission success. Seventeen auditory tasks carried out by British infantry and combat-support personnel were identified through a series of focus groups conducted by Bevis et al. For military personnel, these auditory tasks are termed mission-critical auditory tasks (MCATs) if they are carried in out in a military-specific environment and have a negative consequence when performed below a specified level. A questionnaire study was conducted to find out which of the auditory tasks identified by Bevis et al. satisfy the characteristics of an MCAT. Seventy-nine British infantry and combat-support personnel from four regiments across the South of England participated. For each auditory task participants indicated: 1) the consequences of poor performance on the task, 2) who performs the task, and 3) how frequently the task is carried out. The data were analysed to determine which tasks are carried out by which personnel, which have the most negative consequences when performed poorly, and which are performed the most frequently. This resulted in a list of 9 MCATs (7 speech communication tasks, 1 sound localization task, and 1 sound detection task) that should be prioritised for representation in a measure of auditory fitness for duty (AFFD) for these personnel. Incorporating MCATs in AFFD measures will help to ensure that personnel have the necessary auditory skills for safe and effective deployment on operational duties.

Fit for the frontline? A focus group exploration of auditory tasks carried out by infantry and combat support personnel.

In order to preserve their operational effectiveness and ultimately their survival, military personnel must be able to detect important acoustic signals and maintain situational awareness. The possession of sufficient hearing ability to perform job-specific auditory tasks is defined as auditory fitness for duty (AFFD). Pure tone audiometry (PTA) is used to assess AFFD in the UK military; however, it is unclear whether PTA is able to accurately predict performance on job-specific auditory tasks. The aim of the current study was to gather information about auditory tasks carried out by infantry personnel on the frontline and the environment these tasks are performed in. The study consisted of 16 focus group interviews with an average of five participants per group. Eighty British army personnel were recruited from five infantry regiments. The focus group guideline included seven open-ended questions designed to elicit information about the auditory tasks performed on operational duty. Content analysis of the data resulted in two main themes: (1) the auditory tasks personnel are expected to perform and (2) situations where personnel felt their hearing ability was reduced. Auditory tasks were divided into subthemes of sound detection, speech communication and sound localization. Reasons for reduced performance included background noise, hearing protection and attention difficulties. The current study provided an important and novel insight to the complex auditory environment experienced by British infantry personnel and identified 17 auditory tasks carried out by personnel on operational duties. These auditory tasks will be used to inform the development of a functional AFFD test for infantry personnel.