Measurements Of Loudness Growth Functions In Children And Adults By The Modified Contour Test

Objective To compare the Loudness growth functions of normal-hearing adults and children obtained-in Modified Contour Test in order to determine if there are clinical differences satatistically significant between. And, to utilize the modified Contour test on Chinese adult and child subjects to evaluate its clinical application in China.Finally,this study intend to start a process of collecting the normative data with reference to Chinese population for the better quality of hearing aids fitting. Methods In the case-control study, 20 adults and 20 children with normal hearing were evaluated for the loudness growth functions using the modified Contour test and then retested 10 children selected randomly a week later after the initial test. The test data were then analyzed with ANOVA and t-test. Results In the analysis of the differences between adults and children,we found there are significant differences in almost all loundness categories between them except the comfortable level(F=0.003 P=0.956),and there are significant differences in 500Hz(F=7.784 P=0.006) and 1000Hz(F=10.227 P=0.002),while no significant differences in 2000Hz(F=0.012 P=0.912) and 4000 Hz (F=0.154 P=0.695) between them.In the analysis of all the subjectsinvolved,with each stimulus, the results show the expected increase in mean levels as loudness categories increased,also,the mean levels show peaks at 2000Hz of all categories.There is significant difference in frequencies tested .There are significant diferrences between male and femal subjects in loudness categories and frequencies except 500Hz(F=6.92;P=0.09).In the analysis of chlinren,frequencies revealed significant differences with F=4.276, P=0.008,so did male and femal with F=l7.429, P=0.000.The test-retest reliability analysis show there is almost no significant difference except one subject in his 2000Hz of level 6.Conclusions Age and gender can influence the characteristics of loudness growth functions in npmal hearing people.And a good test-retest reliability was shown when we utilized modified Contour test to children in this study. For children,the modified Contour test appears to offer a more vivid and flexible approach to clinical measurement of loudness perception.The study also provides the normative data of the modified Contour test.For the sake of restoring normal loudness perception of hard-hearing people,the determination for compression characteristics of a hearing aid must take the difference complexion of patients into account,and then use the Visual input/output locator algorithm (VIOLA).