A global measure of sickness behaviour: Development of the Sickness Questionnaire

J Health Psychol. 2018 Sep;23(11):1452-1463. doi: 10.1177/1359105316659917. Epub 2016 Jul 24.

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.

Keywords: Sickness Questionnaire; endotoxin; sickness behaviour; sickness response; validation.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Behavioral Symptoms / diagnosis*
  • Double-Blind Method
  • Endotoxins*
  • Female
  • Humans
  • Illness Behavior / physiology*
  • Inflammation / complications*
  • Male
  • Middle Aged
  • Psychiatric Status Rating Scales / standards*
  • Psychometrics / instrumentation*
  • Reproducibility of Results
  • Surveys and Questionnaires / standards
  • Young Adult

Substances

  • Endotoxins