title: Exploratory and confirmatory factor analysis of the PROMIS pain quality item bank.
abstract: OBJECTIVE
  The assessment of pain sensation and quality is a key component in understanding the experience of individuals with chronic pain. This study evaluated the factor structure of the patient-reported outcome measurement information system (PROMIS) pain quality item bank.
  
  
  METHODS
  As part of the PROMIS project, we developed a pool of 37 pain quality items, based on a review of existing pain questionnaires and development of new items. A web-based survey was designed and completed by 845 members of the general population and 967 individuals with different types of chronic pain. Exploratory factor analysis (EFA) was conducted on a random split-half sample of the data to examine the factor structure of the 37 PROMIS pain quality items in the general population and in a chronic pain sample. A confirmatory factor analysis was conducted in the holdout sample.
  
  
  RESULTS
  The EFA of the pain quality items resulted in comparable six-factor solutions for the general and chronic pain samples: (1) pulling/tugging pain; (2) tingling/numbness pain; (3) sharp/stabbing pain; (4) dull/aching pain; (5) pounding/pulsing pain; and (6) affective pain. The confirmatory factor analysis in the holdout sample supported this factor structure.
  
  
  CONCLUSIONS
  Further research is needed to evaluate the psychometric characteristics of the derived scales based on their factor scores.
authors.affiliation: Center for Health Outcomes Research, United BioSource Corporation, 7101 Wisconsin Ave., Suite 600, Bethesda, MD, 20814, USA, dennis.revicki@unitedbiosource.com.
authors.forename: Dennis A
authors.initials: DA
authors.lastname: Revicki
authors.forename: Karon F
authors.initials: KF
authors.lastname: Cook
authors.forename: Dagmar
authors.initials: D
authors.lastname: Amtmann
authors.forename: Neesha
authors.initials: N
authors.lastname: Harnam
authors.forename: Wen-Hung
authors.initials: WH
authors.lastname: Chen
authors.forename: Francis J
authors.initials: FJ
authors.lastname: Keefe
mesh_terms: D005163:Factor Analysis, Statistical; D005260:Female; D006306:Health Surveys; D006801:Humans; D007256:Information Systems; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care / Q000379:methods*; D010146:Pain / Q000145:classification / Q000523:psychology*; D010147:Pain Measurement; D011594:Psychometrics; D011788:Quality of Life; D012955:Societies, Medical; D012959:Socioeconomic Factors; D011795:Surveys and Questionnaires; D014481:United States