title: A global measure of sickness behaviour: Development of the Sickness Questionnaire.
abstract: Symptoms after inflammatory activation, so-called sickness behaviour, overlap with trans-diagnostic complaints. As no self-report questionnaire to assess sickness behaviour exists, we aimed to develop such an instrument, the Sickness Questionnaire. Items responsive to experimentally induced inflammatory activation (randomized double-blind study endotoxin (0.6 ng/kg) versus placebo, n = 52) were selected and the statistical properties were examined in 172 primary care patients. A principal component analysis indicated a one-factor solution (Cronbach's alpha = .86). This 10-item scale correlated with depression ( β = .41, p < .001), anxiety ( β = .36, p < .001), self-rated health ( β = .28, p < .001) and a single item of feeling sick ( β = .55, p < .001). The results support the adequacy of Sickness Questionnaire as a brief assessment instrument of perceived sickness behaviour.
authors.affiliation: 1 Karolinska Institutet, Sweden.|2 Stockholm University, Sweden.
authors.forename: Anna
authors.initials: A
authors.lastname: Andreasson
authors.affiliation: 1 Karolinska Institutet, Sweden.|3 Karolinska University Hospital, Sweden.
authors.forename: Rikard K
authors.initials: RK
authors.lastname: Wicksell
authors.affiliation: 1 Karolinska Institutet, Sweden.
authors.forename: Karin
authors.initials: K
authors.lastname: Lodin
authors.affiliation: 1 Karolinska Institutet, Sweden.|2 Stockholm University, Sweden.
authors.forename: Bianka
authors.initials: B
authors.lastname: Karshikoff
authors.affiliation: 1 Karolinska Institutet, Sweden.|2 Stockholm University, Sweden.
authors.forename: John
authors.initials: J
authors.lastname: Axelsson
authors.affiliation: 1 Karolinska Institutet, Sweden.|2 Stockholm University, Sweden.
authors.forename: Mats
authors.initials: M
authors.lastname: Lekander
mesh_terms: D000328:Adult; D001526:Behavioral Symptoms / Q000175:diagnosis*; D004311:Double-Blind Method; D004731:Endotoxins; D005260:Female; D006801:Humans; D055809:Illness Behavior / Q000502:physiology*; D007249:Inflammation / Q000150:complications*; D008297:Male; D008875:Middle Aged; D011569:Psychiatric Status Rating Scales / Q000592:standards*; D011594:Psychometrics / Q000295:instrumentation*; D015203:Reproducibility of Results; D011795:Surveys and Questionnaires / Q000592:standards; D055815:Young Adult
chemical_list: D004731:Endotoxins
keywords: Sickness Questionnaire; endotoxin; sickness behaviour; sickness response; validation