3. How is radiofrequency energy exposure measured in epidemiologic studies?
Levels of radiofrequency exposure are indirectly estimated using information from interviews or questionnaires. These measures include the following:
- How “regularly” study participants use cell phones (the minimum number of calls per week or month)
- The age and the year when study participants first used a cell phone and the age and the year of last use (allows calculation of the duration of use and time since the start of use)
- The average number of cell phone calls per day, week, or month (frequency)
- The average length of a typical cell phone call
- The total hours of lifetime use, calculated from the length of typical call times, the frequency of use, and the duration of use