Impact of different hearing aid amplification strategies on speech recognition in hearing impaired Urdu speaking children: A comparative study.

Abstract

BACKGROUND:
Hearing aids are most commonly used for effective amplification in the hearing impaired. Hearing aid technology has rapidly progressed from analogue to digital sound processing devices. However, controversy still exists in connection with the compression strategy most appropriate for better word and speech recognition especially for the Urdu language.

OBJECTIVES:
To compare the three amplification strategies, including peak clipping, compression limiting and wide dynamic range compression, to suggest the most appropriate strategy in hearing aids for moderate and severe hearing loss, for the development of better word recognition in the Urdu language.

METHODOLOGY:
This Quasi-experimental, recruited N=50 children with moderate and severe hearing loss, from Salamat Hospital, Gujranwala from Sept. 2017 to August 2018. The sample of N=50 children included both genders aged 7-15 years, bilaterally fitted with digital programmable, multichannel compression aids, integrating one of three amplification strategies including peak clipping, compression limiting and wide dynamic range compression for at least 1 month in a compensated order across children. After using a specific amplification strategy for at least one week, word recognition score was measured through monosyllabic words in Urdu language. SPSS Ver-20 was used for data analysis.

RESULTS:
Results revealed significant differences (p=0.000) among word recognition score means of 64.40±5.01, 69.00±5.80 & 94.20±5.75 for peak clipping, compression limiting and wide dynamic range compression hearing aid amplification strategies respectively with maximum increase noted for wide dynamic range compression amplification strategy.

CONCLUSION:
Wide-dynamic-range compression (WDRC) fitting strategy is better for word recognition in Urdu speaking population than linear amplification, and output compression for moderate and severe hearing loss in children

KEY WORDS:
Amplification strategies, Compression limiting, Hearing impaired, Hearing aid, Peak Clipping, Wide dynamic Range compression, Word recognition score.