title: Representativeness of the Patient-Reported Outcomes Measurement Information System Internet panel.
abstract: OBJECTIVE
  To evaluate the Patient-Reported Outcomes Measurement Information System (PROMIS), which collected data from an Internet polling panel, and to compare PROMIS with national norms.
  
  
  METHODS
  We compared demographics and self-rated health of the PROMIS general Internet sample (N=11,796) and one of its subsamples (n=2,196) selected to approximate the joint distribution of demographics from the 2000 U.S. Census, with three national surveys and U.S. Census data. The comparisons were conducted using equivalence testing with weights created for PROMIS by raking.
  
  
  RESULTS
  The weighted PROMIS population and subsample had similar demographics compared with the 2000 U.S. Census, except that the subsample had a higher percentage of people with higher education than high school. Equivalence testing shows similarity between PROMIS general population and national norms with regard to body mass index, EQ-5D health index (EuroQol group defined descriptive system of health-related quality of life states consisting of five dimensions including mobility, self-care, usual activities, pain/discomfort, anxiety/depression), and self-rating of general health.
  
  
  CONCLUSIONS
  Self-rated health of the PROMIS general population is similar to that of existing samples from the general U.S. population. The weighted PROMIS general population is more comparable to national norms than the unweighted population with regard to subject characteristics. The findings suggest that the representativeness of the Internet data is comparable to those from probability-based general population samples.
authors.affiliation: UCLA Department of Medicine, Division of General Internal Medicine & Health Services Research, University of California-Los Angeles, 911 Broxton Plaza, Los Angeles, CA 90095, USA. hhliu@ucla.edu
authors.forename: Honghu
authors.initials: H
authors.lastname: Liu
authors.forename: David
authors.initials: D
authors.lastname: Cella
authors.forename: Richard
authors.initials: R
authors.lastname: Gershon
authors.forename: Jie
authors.initials: J
authors.lastname: Shen
authors.forename: Leo S
authors.initials: LS
authors.lastname: Morales
authors.forename: William
authors.initials: W
authors.lastname: Riley
authors.forename: Ron D
authors.initials: RD
authors.lastname: Hays
mesh_terms: D006306:Health Surveys; D006801:Humans; D007256:Information Systems / Q000592:standards / Q000706:statistics & numerical data*; D017063:Outcome Assessment, Health Care / Q000592:standards / Q000706:statistics & numerical data*; D010349:Patient Compliance / Q000706:statistics & numerical data*; D017060:Patient Satisfaction / Q000706:statistics & numerical data*; D012650:Self Disclosure; D011795:Surveys and Questionnaires; D014481:United States