title: A randomised, placebo-controlled trial of transcranial pulsed electromagnetic fields in patients with multiple chemical sensitivity.
abstract: OBJECTIVE
  To evaluate the efficacy of transcranially applied pulsed electromagnetic fields (PEMF) on functional impairments and symptom severity in multiple chemical sensitivity (MCS) patients.
  
  
  METHODS
  The study was conducted as a nationwide trial in Denmark using a randomised, parallel-group, double-blind and placebo-controlled design. Sample size was estimated at 40 participants. Eligibility criteria were age 18-75 years and fulfilment of the MCS case criteria. Participants received either PEMF or placebo PEMF (no stimulation) applied transcranially for 6 weeks. The primary outcome was the Life Impact Scale (LIS) of the Quick Environmental Exposure and Sensitivity Inventory (QEESI). Secondary outcomes were the Symptom Severity Scale (SSS) and the Chemical Intolerance Scale of QEESI.
  
  
  RESULTS
  A total of 39 participants were randomised to PEMF or placebo treatment. No significant difference was observed on QEESI LIS between groups with a mean change score of -5.9 in the PEMF group compared with -1.5 in the placebo group (p=0.35, effect size=-0.31). However, a significant decrease was detected on QEESI SSS within and between groups with a mean change score of -11.3 in the PEMF group compared with -3.2 in the placebo group (p=0.03, effect size=-0.60).
  
  
  CONCLUSIONS
  PEMF treatment of 6 weeks showed no effect on functional impairments in MCS. However, a significant decrease in symptom severity was observed.
authors.affiliation: 1Department of Dermatology and Allergology,Copenhagen University Hospital Gentofte,Hellerup,Denmark.
authors.forename: Marie Thi Dao
authors.initials: MTD
authors.lastname: Tran
authors.affiliation: 1Department of Dermatology and Allergology,Copenhagen University Hospital Gentofte,Hellerup,Denmark.
authors.forename: Sine
authors.initials: S
authors.lastname: Skovbjerg
authors.affiliation: 2Department of Health Science and Technology,Center for Sensory-Motor Interaction,Aalborg University,Aalborg,Denmark.
authors.forename: Lars
authors.initials: L
authors.lastname: Arendt-Nielsen
authors.affiliation: 3Department of Public Health,Section of Biostatistics,University of Copenhagen,Copenhagen K,Denmark.
authors.forename: Karl Bang
authors.initials: KB
authors.lastname: Christensen
authors.affiliation: 1Department of Dermatology and Allergology,Copenhagen University Hospital Gentofte,Hellerup,Denmark.
authors.forename: Jesper
authors.initials: J
authors.lastname: Elberling
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D055909:Magnetic Field Therapy; D008297:Male; D008875:Middle Aged; D018777:Multiple Chemical Sensitivity / Q000150:complications / Q000628:therapy*; D012720:Severity of Illness Index; D016896:Treatment Outcome; D055815:Young Adult
keywords: capsaicin; multiple chemical sensitivity; pulsed electromagnetic fields; randomised trial; treatment