In 2005, a systematic review looked at the results of 31 experiments testing the role of electromagnetic fields in causing ES. Each of these experiments exposed people who reported electromagnetic hypersensitivity to genuine and sham electromagnetic fields under single- or double-blind conditions. The review concluded that:
"The symptoms described by 'electromagnetic hypersensitivity' sufferers can be severe and are sometimes disabling. However, it has proved difficult to show under blind conditions that exposure to electromagnetic fields can trigger these symptoms. This suggests that 'electromagnetic hypersensitivity' is unrelated to the presence of electromagnetic fields, although more research into this phenomenon is required."
Seven studies were found which did report an association, while 24 could not find any association with electromagnetic fields. However, of the seven positive studies, two could not be replicated even by the original authors, three had serious methodological shortcomings, and the final two presented contradictory results. Since then, several more double-blind experiments have been published, each of which has suggested that people who report electromagnetic hypersensitivity are unable to detect the presence of electromagnetic fields and are as likely to report ill health following a sham exposure, as they are following exposure to genuine electromagnetic fields.
One of the studies which Rubin et al. reviewed, known as the Essex study, received some criticism for its methodology and analysis, and the authors responded in full to these initial criticisms. The authors noted that their study says nothing about the long-term effects of exposure to electromagnetic fields, but those affected generally claimed to respond to the fields within a few minutes.
In 2008, another systematic review reached the same conclusion as Rubin et al.
A 2005 report by the UK Health Protection Agency concluded that electromagnetic hypersensitivity needs to be considered in ways other than its etiology; that is, the suffering is real, even if the underlying cause is not thought to be related to electromagnetic fields. They also wrote that considering only whether electromagnetic radiation was a causative factor was not meeting the needs of sufferers, although continued research on etiology was essential.
