Test-retest reliability of the Toy Discrimination Test with a masker of noise or babble in children with hearing impairment

Abstract

Objective: The Toy Discrimination Test measures children's ability to discriminate spoken words. Previous assessments of reliability tested children with normal hearing or mild hearing impairment, and most studies used a version of the test without a masking sound. We assessed test-retest reliability for children with hearing impairment using maskers of broadband noise and two-talker babble. Design: Stimuli were presented from a loudspeaker. The signal-to-noise ratio (SNR) was varied adaptively to estimate the speech-reception threshold (SRT) corresponding to 70.7% correct performance. Participants completed each masked condition twice. Study sample: Fifty-five children with permanent hearing impairment participated, aged 3.0 to 6.3 years. Thirty-four children used acoustic hearing aids; 21 children used cochlear implants. Results: For the noise masker, the within-subject standard deviation of SRTs was 2.4 dB, and the correlation between first and second SRT was + 0.73. For the babble masker, corresponding values were 2.7 dB and + 0.60. Reliability was similar for children with hearing aids and children with cochlear implants. Conclusions: The results can inform the interpretation of scores from individual children. If a child completes a condition twice in different listening situations (e.g. aided and unaided), a difference between scores ≥ 7.5 dB would be statistically significant (p <.05).

Key Words::

• Reliability
• speech perception
• children
• hearing impairment

Acknowledgements

This work was supported by Action on Hearing Loss (G48Vickers). We are sincerely grateful to participating children and their parents. We used speech stimuli from the IHR-McCormick automated toy test, which was developed at the Medical Research Council Institute of Hearing Research, Nottingham, UK. We thank the following organizations for recruiting participants: Bradford Teaching Hospitals NHS Foundation Trust, Brighton and Sussex University Hospitals NHS Trust, Great Ormond Street Hospital for Children NHS Foundation Trust, Guy's & St Thomas’ NHS Foundation Trust, Homerton University Hospital NHS Foundation Trust, Imperial College Healthcare NHS Trust, Royal Berkshire NHS Foundation Trust, Royal Surrey County Hospital NHS Foundation Trust, St George's Healthcare NHS Trust, University College London Hospitals NHS Foundation Trust, Whipps Cross University Hospital NHS Trust, Essex Special Educational Needs Service, Hertfordshire Specialist Advisory Service, West Sussex Sensory Support Team, Children's Hearing Evaluation and Amplification Resource, Cochlear Implanted Children's Support Group, and the National Deaf Children's Society. The AB-York Crescent of Sound was provided by Advanced Bionics AG and the University of York.

Declaration of interest: The authors report no declarations of interest.