The aim of the study was to investigate the effects of radiation from cell phones on the hearing of users. Three groups of men were tested. The first were frequent users (approximately 2 hours a day for 4 years). The second were moderate users (10-20 minutes a day for 4 years), and the third group was non-users. Subjects were excluded who had ear pathologies or who had been exposed to loud noises. There were 20 men in each group.
Brain stem evoked response audiometry (BERA) and pure tone audiometry (PTA) were the tests used to assess hearing
There were no significant differences between the groups in BERA testing. The PTA tests showed significant hearing loss at 4,000 Hz in the right ears, and at 500 and 4,000 Hz in the left ears. Most subjects used both ears equally to use the phone, so that statistical analysis could not be performed on laterality of use.
study does not appear to have been carried out in a blinded fashion.
Also, there may have been other characteristics of the frequent-user
group that had an influence on the outcome, such as additional exposure
to noise. Multiple comparisons were made, and no correction seems
to have been made for this.