title: Effects of personalised exposure on self-rated electromagnetic hypersensitivity and sensibility - A double-blind randomised controlled trial.
abstract: Previous provocation experiments with persons reporting electromagnetic hypersensitivity (EHS) have been criticised because EHS persons were obliged to travel to study locations (seen as stressful), and that they were unable to select the type of signal they reported reacting to. In our study we used mobile exposure units that allow double-blind exposure conditions with personalised exposure settings (signal type, strength, duration) at home. Our aim was to evaluate whether subjects were able to identify exposure conditions, and to assess if providing feedback on personal test results altered the level of self-reported EHS.
  
  
  
  We used double-blind randomised controlled exposure testing with questionnaires at baseline, immediately before and after testing, and at two and four months post testing. Participants were eligible if they reported sensing either radiofrequency or extremely low frequency fields within minutes of exposure. Participants were visited at home or another location where they felt comfortable to undergo testing. Before double-blind testing, we verified together with participants in an unblinded exposure session that the exposure settings were selected were ones that the participant responded to. Double-blind testing consisted of a series of 10 exposure and sham exposures in random sequence, feedback on test results was provided directly after testing.
  
  
  
  42 persons participated, mean age was 55years (range 29-78), 76% were women. During double-blind testing, no participant was able to correctly identify when they were being exposed better than chance. There were no statistically significant differences in the self-reported level of EHS at follow-up compared to baseline, but during follow-up participants reported reduced certainty in reacting within minutes to exposure and reported significantly fewer symptoms compared to baseline.
  
  
  
  Our results suggest that a subgroup of persons exist who profit from participation in a personalised testing procedure.
authors.affiliation: Department of Environmental Health, Public Health Service of Amsterdam (GGD), Amsterdam, The Netherlands.
authors.forename: Imke
authors.initials: I
authors.lastname: van Moorselaar
authors.affiliation: Department of General Practice and Elderly Care, EMGO+ Institute for Health and Care Research, VU University Medical Center, Amsterdam, The Netherlands; Institute for Risk Assessment Sciences, Utrecht University, Utrecht, The Netherlands.
authors.forename: Pauline
authors.initials: P
authors.lastname: Slottje
authors.affiliation: Offically recognised psychotherapist, Zurich, Switzerland.
authors.forename: Pia
authors.initials: P
authors.lastname: Heller
authors.affiliation: Department of Environmental Health, Public Health Service of Amsterdam (GGD), Amsterdam, The Netherlands.
authors.forename: Rob
authors.initials: R
authors.lastname: van Strien
authors.affiliation: Institute for Risk Assessment Sciences, Utrecht University, Utrecht, The Netherlands.
authors.forename: Hans
authors.initials: H
authors.lastname: Kromhout
authors.affiliation: IT'IS Foundation, Zurich, Switzerland.
authors.forename: Manuel
authors.initials: M
authors.lastname: Murbach
authors.affiliation: IT'IS Foundation, Zurich, Switzerland; Swiss Federal Institute of Technology (ETH), Zurich, Switzerland.
authors.forename: Niels
authors.initials: N
authors.lastname: Kuster
authors.affiliation: Institute for Risk Assessment Sciences, Utrecht University, Utrecht, The Netherlands; Julius Centre for Public Health Sciences and Primary Care, University Medical Centre, Utrecht, The Netherlands.
authors.forename: Roel
authors.initials: R
authors.lastname: Vermeulen
authors.affiliation: Institute for Risk Assessment Sciences, Utrecht University, Utrecht, The Netherlands; Institute for Social and Preventive Medicine, Bern, Switzerland. Electronic address: a.huss@uu.nl.
authors.forename: Anke
authors.initials: A
authors.lastname: Huss
mesh_terms: D000328:Adult; D000368:Aged; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D006967:Hypersensitivity / Q000209:etiology*; D008297:Male; D008875:Middle Aged; D000069079:Radiation Exposure; D011846:Radio Waves / Q000009:adverse effects*; D057566:Self Report
keywords: Electromagnetic hypersensitivity; Exposure testing; Personalised testing; Randomised controlled trial