Fit for duty? Hannah Semeraro,

Transcription

1 Fit for duty? Hannah Semeraro,

2 The Team PhD Students Funded by Zoe Bevis Supervisory Team Matthew Blyth Hannah Semeraro Dr Daniel Rowan Dr Rachel van Besouw Dr Ben Lineton Dr Adrian Allsopp 2

3 What is Auditory Fitness for Duty (AFFD)? 3

4 Current measure of AFFD Smoorenburg

5 Overview (1) Identifying mission critical auditory tasks (MCATs) (2) Introducing a new speech communication fitness-for-duty test (3) Next steps 5

6 (1) Identifying mission critical auditory tasks (MCATs) 6

7 (1) Identifying MCATs Stage 1: Exploration of auditory tasks Stage 2: Determination of MCATs Method Focus groups infantry personnel Range of ranks Active service experience Qualitative analysis Results Seventeen auditory tasks Speech communication (8) e.g. hearing grid references Sound localisation (6) e.g. locating a talker Sound interpretation (3) e.g. determining talker identity Bevis ZB, Semeraro HS, et al. Fit for the frontline? A focus group exploration of auditory tasks carried out by infantry and combat support personnel. Noise and Health 14;16:

8 (1) Identifying MCATs Stage 1: Exploration of auditory tasks Stage 2: Determination of MCATs Method Questionnaire 87 infantry personnel Quantitative analysis Likert scale ratings for 1. Who performs the task 2. Consequences of poor performance on the task 3. Frequency of task Zoë Bevis- Abstract ID 327 Results 8 MCATs Speech Communication - Accurately hearing commands in a casualty situation - Accurately hearing grid references - Accurately hearing directions on patrol - Accurately hearing directions in a vehicle - Accurately hearing fire control orders - Accurately hearing stop commands - Accurately hearing the briefing before a foot patrol Sound Localisation - Locating a small arms firing point 8

9 (2) Introducing a new speech communication fitness for duty test 9

10 (2) Introducing new speech test Which test? Chosen test Equalising stimuli Adaptive procedure Review of existing speech tests Thoroughly reviewed long list of existing speech tests Particularly in terms of face validity Gathered opinions of military subject-matter experts - All had experience issuing commands - Speech test stimuli rated on relevance to command structure 1

11 (2) Introducing new speech test Which test? Chosen test Equalising stimuli Adaptive procedure THE COORDINATE RESPONSE MEASURE Re-recorded e.g. using NATO call signs with a British accent Removed disyllabic number seven Increased number of target words Using steady speech-spectrum noise initially 11

12 First: equalised RMS level (2) Introducing new speech test Which test? Chosen test Equalising stimuli Adaptive procedure 1 Callsigns (1) 1 Callsigns (1) 1 Callsigns (2) 1 Callsigns (2) First: equalised RMS level FOXTROT Colours (1) 1 BRAVO Colours (1) Colours (2) Colours (2) 1 intelligibility Second: equalised speech Second: equalised speech intelligibility 1 Numbers (1) 1 Numbers (1) 1 Numbers (2) 1 Numbers (2)

13 (2) Introducing new speech test Which test? Chosen test Equalising stimuli Adaptive procedure Questions: How precise is the CRM as a speech-in-noise test? What is the best CRM scoring method? What is the concurrent validity of CRM when compared to the Triple-Digit-Test (TDT)? Method: Normal hearing (n=3) and hearing impaired (n=22) listeners Three test conditions: CRM with two scoring methods and TDT Tw-down-one-up adaptive procedure, speech-spectrum noise Repeated measures (normal hearing 4 repeats, hearing impaired 2 repeats) 13

14 (2) Introducing new speech test Which test? Chosen test Equalising stimuli Adaptive procedure Test condition Typical measurement error (95% confidence interval, db) Correlation with TDT (Pearson s r) Normal hearing Hearing impaired Normal hearing & hearing impaired CRM (callsigns on) CRM (callsigns off) Triple-Digit-Test / 14

15 (3) Next step: external validation of CRM fitness for duty test 15

16 (3) Next step External validation: comparing performance on the CRM with performance on simulated operational tasks Laboratory simulation of MCATs commands recorded using KEMAR wearing a military radio Processed through hearing loss simulator TONIGHT S AMBUSH WILL BE AT GRID MOVE INTO THE WOOD LINE AND GO FIRM AT THE FORK IN THE TRACK GO LEFT I REQUIRE THE MEDIC AT MY LOCATION NOW 16

17 Thank you