Comparative study in detection of severe hearing loss in developmentally retarded children :
This study was taken up to compare the hearing threshold in developmentally retarded children with severe hearing loss using conventional audiometry and brain stem evoked response audiometry. Using BERA the hearing threshold in decibles(dB) of each ear was found seperately (Based on appearance of wave V at minimum stimulus intensity). Pure Tone Audiometry was used to measure hearing acuity over a range of frequencies (500 – 6000 Htz). The results were plotted on an audiogram, which displayed the auditory threshold at each frequency for each ear. Statistical analysis was done by using descriptive and inferential statistics using Kolmogorov Smirnov Z Test and Mann Whitney U test. p<0.05 was considered as level of significance. 55% of the study subjects were female. 40% of the subjects were in the age group of 6 – 8 years & 60 % were in the 9 – 12 years age group. Majority of them ( 80%) were from low socioeconomic class. Report of Pure tone audiometry findings showed that maximum cases were having a hearing threshold ≥ 100 dB ( 35%). 15% of the subjects had a hearing threshold of 90 dB and in 20% of the subjects, the hearing threshold was 20%. The study showed inconclusive finding for 30 % of the cases.