A prospective cohort study was conducted in Australia to investigate associations between the use of mobile phones and cordless phones among primary school children and effects on their cognitive function.
|Reference group 1||no change or decrease of mobile phone use between baseline and follow-up|
|Group 2||increase of mobile phone use between baseline and follow-up|
|Reference group 3||no change or decrease of cordless phone use between baseline and follow-up|
|Group 4||increase of cordless phone use between baseline and follow-up|
|Participation rate||66.5 %|
Of 412 children, a larger proportion of them used a cordless phone (76% at baseline and follow-up), compared to a mobile phone (parental report: 31% at baseline and 43% at follow-up; children reports: 57% at baseline and 68% at follow-up). The median numbers of voice calls weekly for mobile phone and cordless phone were both 2 at baseline, and 2.5 and 2 at follow-up, respectively.
Of 26 comparisons of changes in cognitive outcomes, four demonstrated significant associations. The increase in mobile phone usage was associated with a reduced response time for response inhibition, a reduced number of total errors for spatial problem solving and increased response time for a Stroop interference task. Except for a reduced detection task accuracy, the increase in cordless phone usage had no effect on the changes in cognitive outcomes. Due to the small numbers of mobile and cordless phone calls, the observed changes in cognitive tasks could be pure chance findings.
The authors conclude that they found limited evidence that change in mobile phone use or cordless phone use in primary school children was associated with change in cognitive function.
Exposure assessment of phone use is based on parental and childrens' reports.