Improving the performance of the New Zealand Hearing Screening Test. (2020)
Type of ContentTheses / Dissertations
Degree NameMaster of Audiology
PublisherUniversity of Canterbury
AuthorsSpence, Kent J.show all
Hearing impairment adversely affects many individuals. Within New Zealand the number of individuals who will struggle with hearing loss is expected to increase significantly in the coming years due to our ageing population (Exeter, Wu, Lee, & Searchfield, 2015). Hearing impairment has been shown to have detrimental effects on psychosocial outcomes, and is related to higher rates of depression (Gopinath et al., 2009), a reduction in independence (Schneider et al., 2010), poorer employment outcomes (Winn, 2007), and is associated with higher rates of cognitive decline (Lin et al., 2013). Early identification and intervention is needed to manage this rising healthcare need. Hearing screening tests have been shown to be efficacious and cost effective in the early identification of hearing impairment and have been attributed to an increased uptake of hearing aid use (Liu, Collins, Souza, & Yueh, 2011; Yueh et al., 2010).
The present study looks to improve the performance of the New Zealand Hearing Screening Test (NZHST) – a publically available hearing screening tool that was initially developed in 2011. The present study aimed to assess whether there were any advantages in applying Brand & Kollmeier’s A1 procedure to the digit triplet. This adaptive procedure was incorporated into the NZHST and administered to 33 participants (18 with normal hearing, and 15 with hearing impairment) alongside the standard 1-up 1-down procedure currently used. In the present study data collected also allowed for concurrent estimation of SRT for three different scoring methods – the current “average of the last 20 SNRs” method, and the estimation of thresholds by the fitting of psychometric functions to the triplet- and digit- scoring data.
Analyses of the data showed that overall performance in the present study was poor. The Brand & Kollmeier A1 procedure gave a test sensitivity of 62% and a specificity of 95%. The 1-up 1-down procedure gave a test sensitivity of 71% and a specificity of 80%. This result is incongruent with previous studies suggesting that the NZHST has a test sensitivity and specificity of 94% and 88% respectively (Bowden, 2013). Further investigation will be required to determine the cause of this discrepancy.