title: Factor Analysis of the DePaul Symptom Questionnaire: Identifying Core Domains.
abstract: The present study attempted to identify critical symptom domains of individuals with Myalgic Encephalomyelitis (ME) and chronic fatigue syndrome (CFS). Using patient and control samples collected in the United States, Great Britain, and Norway, exploratory factor analysis (EFA) was used to establish the underlying factor structure of ME and CFS symptoms. The EFA suggested a four-factor solution: post-exertional malaise, cognitive dysfunction, sleep difficulties, and a combined factor consisting of neuroendocrine, autonomic, and immune dysfunction symptoms. The use of empirical methods could help better understand the fundamental symptom domains of this illness.
authors.affiliation: DePaul University, USA.
authors.forename: Leonard A
authors.initials: LA
authors.lastname: Jason
authors.affiliation: DePaul University, USA.
authors.forename: Madison
authors.initials: M
authors.lastname: Sunnquist
authors.affiliation: DePaul University, USA.
authors.forename: Abigail
authors.initials: A
authors.lastname: Brown
authors.affiliation: DePaul University, USA.
authors.forename: Jacob
authors.initials: J
authors.lastname: Furst
authors.affiliation: DePaul University, USA.
authors.forename: Marjoe
authors.initials: M
authors.lastname: Cid
authors.affiliation: DePaul University, USA.
authors.forename: Jillianna
authors.initials: J
authors.lastname: Farietta
authors.affiliation: DePaul University, USA.
authors.forename: Bobby
authors.initials: B
authors.lastname: Kot
authors.affiliation: DePaul University, USA.
authors.forename: Craig
authors.initials: C
authors.lastname: Bloomer
authors.affiliation: DePaul University, USA.
authors.forename: Laura
authors.initials: L
authors.lastname: Nicholson
authors.affiliation: DePaul University, USA.
authors.forename: Yolonda
authors.initials: Y
authors.lastname: Williams
authors.affiliation: DePaul University, USA.
authors.forename: Rachel
authors.initials: R
authors.lastname: Jantke
authors.affiliation: Newcastle University, UK.
authors.forename: Julia L
authors.initials: JL
authors.lastname: Newton
authors.affiliation: Oslo University Hospital, Norway.
authors.forename: Elin Bolle
authors.initials: EB
authors.lastname: Strand
keywords: Case definition; Chronic fatigue syndrome; DePaul symptom questionnaire; Myalgic encephalomyelitis