These authors performed a study of the effect of RF exposure on cognitive function that was designed to improve on the deficiencies seen in other similar studies. They had a large sample size, which increase the statistical power and reduced the risk of false positive and false negative results. Their study was double blind, reducing the chance of the findings being influenced by an outside factor.
On hundred and sixty-eight healthy volunteers were tested, of whom 99 were women. Average age was 23.5 years. Each was tested in two sessions, one week apart. In one session they were exposed to RF fields. A random half were exposed to GSM modulated signal and the other half to CW unmodulated signal. Both were at 888 MHz, and the average SAR was 1.4 W/kg. In the other session they were sham-exposed. Half of the participants were RF-exposed in the first session, and half in the second. Neither the participant nor the experimenter was aware of the on-off exposure condition, which was allocated in a counterbalanced order. A mobile phone was fixed to the head on a "cage-cap". It was on the left side for half the participants, and on the right for the other half.
Four tasks were performed, each after a training phase. These were a simple reaction time task, a choice reaction time task, a subtraction task, and a vigilant task.
authors found no significant effect of the RF exposure on any of the
tasks. The results were no different, irrespective of the type of
RF signal (GSM or CW), the side of the head of the RF exposure, or
the gender of the subject.