§ Mr. Michael McNair-Wilsonasked the Secretary of State for Social Services what tests his Department employs for measur- 292W ing hearing normalcy; and if a scale of normal hearing on age basis has been produced.
§ Mr. AlisonMy Department does not employ such tests, but I am advised that simple tests usually include conversational voice and forced whisper tests at various distances and pure tone audiometry. These are often supplemented by speech audiometry using phonetically balanced word lists and sentences at different levels of amplification. From these audiometric tests research workers have developed average score lists for speech discrimination in relation to age. I understand that the results of research work showing the average hearing loss with age are available to expert workers in the field.