title: Validity of the Patient Generated Index as a quality-of-life measure in radiation oncology.
abstract: OBJECTIVE
  To evaluate psychometric properties of an instrument designed to measure individualized health-related quality of life (HRQOL).
  
  
  METHODS
  Repeated measures of self-reported quality of life.
  
  
  METHODS
  An outpatient radiation therapy department in the western part of the United States.
  
  
  METHODS
  86 adults with cancer receiving their first course of radiation therapy.
  
  
  METHODS
  The Patient Generated Index (PGI), the National Comprehensive Cancer Network's Distress Thermometer (DT), and the European Organisation for Research and Treatment of Cancer Quality-of-Life Questionnaire-Core-30 (QLQ-C30).
  
  
  METHODS
  Convergent validity, responsiveness, sensitivity, and response shift.
  
  
  RESULTS
  PGI scores were inversely correlated with scores on the DT (r = -0.49, -0.55, -0.44; p < 0.001), as well as the role (r = 0.31, 0.4, 0.38; p < 0.01), emotional (r = 0.33, 0.41, 0.33; p < 0.01), social functioning (r = 0.27, 0.49, 0.42; p < 0.05), pain (r = -0.29, -0.39, -0.39; p < 0.01), and fatigue (r = -0.35, -0.25, -0.47; p < 0.05) QLQ-C30 subscales at all measurement times. The PGI was responsive to those reporting high or low DT scores (t = 4.42, 3.32, 2.9; p < 0.05). A small-to-moderate effect size was detected in those who had an increase (effect size = 0.51) or decrease (effect size = 0.38) in HRQOL over time. Participants reconceptualized HRQOL over time.
  
  
  CONCLUSIONS
  Data supported the PGI as a valid measure of individualized HRQOL.
  
  
  CONCLUSIONS
  The PGI potentially provides a more patient-centered measure of HRQOL in patients with cancer. Additional testing is needed in larger, more diverse groups.
authors.affiliation: Saint Alphonsus Regional Medical Center, Boise, ID, USA. susatave@sarmc.org
authors.forename: Susan S
authors.initials: SS
authors.lastname: Tavernier
authors.forename: Susan L
authors.initials: SL
authors.lastname: Beck
authors.forename: Margaret F
authors.initials: MF
authors.lastname: Clayton
authors.forename: Marjorie A
authors.initials: MA
authors.lastname: Pett
authors.forename: Donna L
authors.initials: DL
authors.lastname: Berry
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000451:nursing / Q000523:psychology* / Q000532:radiotherapy*; D009859:Oncology Nursing / Q000379:methods; D010045:Outpatients / Q000523:psychology; D011446:Prospective Studies; D011594:Psychometrics / Q000592:standards*; D011788:Quality of Life; D011878:Radiotherapy / Q000451:nursing / Q000523:psychology*; D015203:Reproducibility of Results; D011795:Surveys and Questionnaires / Q000592:standards*; D055815:Young Adult