EFFECT OF AGE ON UNILATERAL AND BILATERAL EDULINK FITTING IN NORMAL HEARING SUBJECTS

Mukari SZ, Umat C, Abdul Razak UA, Mannan NH, Mohamad S.

Department of Audiology & Speech Sciences, Universiti Kebangsaan Malaysia, Malaysia.

This study examined the age effect on the benefit obtained from unilateral and bilateral Edulink usage. Measurements were conducted on 66 normal hearing subjects consisted of 22 children (8 to 9 years old), 22 young adults (aged 20-30 years old), and 22 older adults (50 to 60 years old). Reception threshold for sentences (RTS) was measured  using the Malay Hearing in Noise Test (HINT) in three listening conditions: no-Edulink, unilateral and in bilateral Edulink fittings.  Edulink benefit was defined as the improvement in RTS with the Edulink usage as compared to without the Edulink. A mixed repeated measure ANOVA revealed that for all age groups, there was a significant main effect of listening conditions F(1.76, 108.98) = 14.72, p<0.001, in which the mean RTS without Edulink was significantly poorer than those obtained in unilateral (p<0.001) and in bilateral Edulink fitting (p<0.001). However, there was no significant difference between the mean RTS values in unilateral and bilateral groups (p>0.05).  A significant interaction between listening condition and age group was also present signifying differential effects of age group on the RTS values in different listening conditions.  A one way ANOVA was conducted to examine the effect of age groups on Edulink benefits. There were significant main effects of age groups in unilateral benefit (F (2, 63)=12.14, p<0.001) and in bilateral fitting (F(2,63)=15.40, p<0.001). Unilateral fitting revealed that children and older adults received significantly greater benefit than did young adults (p<0.01), while for bilateral fitting, children received a significantly higher benefit than both adult groups (p<0.05). This study has demonstrated that age has a significant effect on the magnitude of benefit from edulink usage.  Bilateral fitting did not provide a significantly better RTS than unilateral fitting for all age groups.

E-mail: szmais@medic.ukm.my