The development and evaluation of the Finnish digit triplet test

AbstractObjectives: The aim of the study was to develop a reliable and easily accessible screening test for primary detection of hearing impairment.Methods: Digits 0–9 were used to form quasirandom digit triplets. First, digit specific intelligibility functions and speech recognition thresholds (SRTs) were determined. To homogenize the test material digits with steep intelligibility function slopes were chosen and level correction up to ±2 dB were applied to the digits as needed. Evaluation measurements were performed to check for systematic differences in intelligibility between the test lists and to obtain normative reference function for normal-hearing listeners.Results: The mean SRT and the final slope of the test lists were −10.8 ± 0.1 dB signal-to-noise ratio (SNR) and 21.7 ± 1.8%/dB, respectively (measurements at constant level; inter-list variability). The mean SRT and slope of the test subjects were −10.8 ± 0.5 dB SNR and 23.4 ± 5.2%/dB (measurements at constant level; inter-subject variability)....