title: Functional rating index: a new valid and reliable instrument to measure the magnitude of clinical change in spinal conditions.
abstract: METHODS
  A prospective cohort design was used to evaluate the Functional Rating Index in a multicentered setting with 139 participants. The Functional Rating Index is a self-reporting instrument consisting of 10 items, each with 5 possible responses that express graduating degrees of disability.
  
  
  OBJECTIVE
  The goal of this study was to evaluate the psychometric qualities of the Functional Rating Index.
  
  
  BACKGROUND
  The Functional Rating Index combines the concepts of the Oswestry Low Back Disability Questionnaire and the Neck Disability Index and seeks to improve on clinical utility (time required for administration).
  
  
  METHODS
  One hundred thirty-nine subjects with spinal complaints participated in four different cohorts to study reliability, validity, responsiveness, and clinical utility.
  
  
  RESULTS
  Reliability: Test-retest: Intraclass correlation coefficient was excellent (ICC3,k = 0.99); interitem correlation: Item efficiency was good, ranging between 0.54 and 0.82, with a moderate correlation among all items; Cronbach's alpha was excellent (0.92).
  
  
  RESULTS
  construct: The Functional Rating Index correlated with the Disability Rating Index (0.76), the Short Form-12 Physical Component Score (0.76), and the Short Form-12 Mental Component Score (0.36). Responsiveness: Overall, the size effect was 1.24, which is commendable. Clinical utility: Time required by the patient and staff averaged 78 seconds per administration, which is noteworthy. Effect of Sociodemographics: Total scores were not affected by education, gender, nor age, suggesting minimal external validity bias.
  
  
  CONCLUSIONS
  The Functional Rating Index appears to be psychometrically sound with regard to reliability, validity, and responsiveness and is clearly superior to other instruments with regard to clinical utility. The Functional Rating Index is a promising useful instrument in the assessment of spinal conditions.
authors.affiliation: Institute of Evidence-Based Chiropractic, Prescott, Arizona; and Palmer College of Chiropractic-West, San Jose, CA, USA. rjf@chiroevidence.com
authors.forename: R J
authors.initials: RJ
authors.lastname: Feise
authors.forename: J
authors.initials: J
authors.lastname: Michael Menke
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D016009:Chi-Square Distribution; D002648:Child; D015331:Cohort Studies; D005260:Female; D006801:Humans; D017116:Low Back Pain / Q000523:psychology / Q000628:therapy; D008297:Male; D008875:Middle Aged; D019547:Neck Pain / Q000523:psychology / Q000628:therapy; D010147:Pain Measurement / Q000379:methods*; D011446:Prospective Studies; D011594:Psychometrics; D015203:Reproducibility of Results