AMTASTM and user-operated smartphone research application audiometry-An evaluation study

To evaluate two user-operated audiometry methods, the AMTASTM PC-based audiometry and a low-cost smartphone audiometry research application (R-App).

A repeated-measures within-subject study design was used to compare both user-operated methods to traditional manual audiometry and to evaluate test-retest reliability of each method.

58 subjects were recruited in the study of which 83 ears had normal hearing thresholds and 33 ears had hearing loss (pure-tone average > 25 dB HL). Average age of participants was 44.8 years, with an age range of 11-85.

Standard deviation of absolute differences ranged between 3.9-6.9 dB on AMTASTM and 4.5-6.8 dB on the R-App. The highest variability was found at the 8000 Hz frequency (R-App and AMTASTM test) and 3000 Hz frequency (AMTASTM retest). Evaluation of test-retest reliability of AMTASTM and R-App showed SD of absolute differences ranging between 3.5-5.8 dB and 3.1-5.0 dB, respectively. The mean threshold difference between test and retest was within ±1.5 dB on AMTASTM and ±1 dB on the R-App.

Accuracy of AMTASTM and the R-App was within acceptable limits for audiometry and comparable to traditional manual audiometry on all tested frequencies (250-8000 Hz). Evaluation of test-retest reliability showed acceptable variation on both AMTASTM and R-App. Both user-operated methods could be reliably performed in a quiet non-soundproofed environment.