Table 4.
Auditory measures
| Breachers* | Engineers* | Normal | Site | p-value | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Variables | S 1 | N 2 | Mean3 | SD4 | S 1 | N 2 | Mean3 | SD4 | Range | MCB5 | WRB6 | Slope7 | Participant8 | Site9 | |||
| Audiometry | |||||||||||||||||
| 0.5K-1K-2K PTA (dB) | 11 | 58 | 7.68 | (3.29) | 4 | -23 | 5.46 | (3.26) | 0.0 | - | 20.0 | 56 | 25 | 0.80 | 0.13 | 0.42 | |
| 2K-4K-8K PTA (dB) | 11 | 58 | 11.48 | (7.07) | 4 | -24 | 8.55 | (3.60) | 0.0 | - | 20.0 | 56 | 26 | 0.84 | 0.46 | 0.01 | |
| AC Threshold - 0.25 kHz (dB HL) | 11 | 57 | 7.42 | (2.54) | 4 | -24 | 10.23 | (9.05) | 0.0 | - | 20.0 | 55 | 26 | 0.46 | 0.36 | 0.17 | |
| AC Threshold - 0.5 kHz (dB HL) | 11 | 57 | 6.57 | (3.63) | 4 | -24 | 4.44 | (3.25) | 0.0 | - | 20.0 | 55 | 26 | 0.81 | 0.13 | 0.57 | |
| AC Threshold - 1 kHz (dB HL) | 11 | 57 | 7.73 | (3.38) | 4 | -24 | 5.35 | (2.77) | 0.0 | - | 20.0 | 55 | 26 | 0.46 | 0.16 | 0.20 | |
| AC Threshold - 2 kHz (dB HL) | 11 | 57 | 6.45 | (4.69) | 4 | -24 | 5.70 | (3.22) | 0.0 | - | 20.0 | 55 | 26 | 0.61 | 0.78 | 0.52 | |
| AC Threshold - 3 kHz (dB HL) | 11 | 57 | 13.33 | (9.55) | 4 | -24 | 8.34 | (5.47) | 0.0 | - | 20.0 | 55 | 26 | 0.41 | 0.33 | 0.14 | |
| AC Threshold - 4 kHz (dB HL) | 11 | 57 | 15.63 | (10.60) | 4 | -24 | 8.94 | (4.83) | 0.0 | - | 20.0 | 55 | 26 | 0.38 | 0.27 | 0.17 | |
| AC Threshold - 6 kHz (dB HL) | 11 | 57 | 18.28 | (12.03) | 4 | -24 | 11.60 | (4.38) | 0.0 | - | 20.0 | 55 | 26 | 0.92 | 0.27 | 0.39 | |
| AC Threshold - 8 kHz (dB HL) | 11 | 57 | 15.19 | (12.48) | 4 | -24 | 12.87 | (6.43) | 0.0 | - | 20.0 | 55 | 26 | 0.41 | 0.73 | 0.00 | |
| AC Threshold - 12 kHz (dB HL) | 11 | 55 | 28.18 | (19.38) | 4 | -23 | 20.39 | (6.70) | 0.0 | - | 20.0 | 54 | 24 | 0.74 | 0.62 | 0.03 | |
| Immitance and Otoacoustic Emissions | |||||||||||||||||
| Abnormal Tymp | 10 | 13 | 10.00 | (31.62) | 4 | -11 | 8.33 | (16.67) | 0 | 24 | 0.92 | ||||||
| Abnormal Acoustic Reflex | 10 | 14 | 0.42 | (1.32) | 4 | -11 | 2.06 | (2.65) | 0 | 25 | 0.39 | 0.14 | |||||
| DPOAE Average (dB) | 9 | 44 | 4.00 | (2.84) | 4 | -22 | 4.96 | (2.16) | 49 | 17 | 0.78 | 0.81 | 0.01 | ||||
| Central Auditory Processing | |||||||||||||||||
| SSW- Left Non-Competing | 10 | 13 | 0.04 | (0.04) | 4 | -11 | 0.03 | (0.04) | 0.0 | - | 0.05 | 0 | 24 | 0.72 | 0.69 | ||
| SSW-Right Non-Competing | 10 | 13 | 0.05 | (0.11) | 4 | -11 | 0.06 | (0.06) | 0.0 | - | 0.05 | 0 | 24 | 0.42 | 0.93 | ||
| SSW-Right Competing | 10 | 13 | 0.10 | (0.16) | 4 | -10 | 0.07 | (0.07) | 0.0 | - | 0.10 | 0 | 23 | 0.28 | 0.72 | ||
| SSW- Left Competing | 10 | 13 | 0.18 | (0.31) | 4 | -11 | 0.12 | (0.12) | 0.0 | - | 0.20 | 0 | 24 | 0.46 | 0.71 | ||
| Gaps in Noise Threshold (ms) | 8 | 8 | 5.06 | (0.98) | 3 | -3 | 5.33 | (3.33) | 0.0 | 8.0 | 0 | 11 | 0.83 | ||||
| 500 Hz MLD (dB) | 9 | 12 | 14.00 | (1.50) | 4 | -10 | 13.25 | (3.40) | 7.3 | - | 16.7 | 0 | 22 | 0.88 | 0.58 | ||
| 500 Hz NoSo Threshold (dB) | 9 | 12 | -13.33 | (2.29) | 4 | -10 | -12.75 | (2.81) | -14.4 | - | -8.2 | 0 | 22 | 0.88 | 0.70 | ||
| 500 Hz NoSpi Threshold (dB) | 9 | 12 | -27.33 | (2.00) | 4 | -10 | -26.00 | (0.98) | -29.0 | - | -18.9 | 0 | 22 | 0.42 | 0.24 | ||
* groups tested; S1 =number of subjects tested; N2-number of measurements; Mean3 = Mean; SD4 =SD; MCB5 = onsite measurements at MCB Quantico; WRB6 = baseline measurements at Walter Reed Bethesda; S 7= slope of the variable over time; Subject 7 = difference between Breacher and Engineer groups, and Site 9 = the difference between on-site and baseline measurements.