title: ASPECTS OF PATIENT REPORTED OUTCOMES IN RARE DISEASES: A DISCUSSION PAPER.
abstract: OBJECTIVE
  A patient reported outcome (PRO) is "any report of the status of a patient's health condition that comes directly from the patient without interpretation of the patient's response by a clinician or anyone else" (USFDA 2009). PROs are discussed widely, and many regard the patients' perspective on treatment benefit as very valuable. Although many PROs have shown satisfactory measurement properties including reliability, validity, and responsiveness, there is great concern about risk of bias, that is, in clinical trials.
  
  
  METHODS
  Differences in perspectives of PRO measurement in rare diseases are given arising from methodology, clinical, HTA, and patient advocacy views.
  
  
  RESULTS
  PROs are playing an important role in dealing with treatment benefit especially in small sample size as occurring often in rare diseases. Challenges remain especially regarding lack of responsiveness of generic measures, limited capture of all patient relevant aspects, study design and high risk of bias.
  
  
  CONCLUSIONS
  PROs seem a valuable instrument to detect patient relevant aspects in rare diseases. They should be seen in addition to other approved assessment methods as randomized controlled trials but not as their substitute.
authors: Institut für Qualität und Wirtschaftlichkeit im Gesundheitswesen (IQWiG)alric.ruether@iqwig.de.
authors: Alric
authors: A
authors: Rüther
authors: Shaare Zedek Medical Center.
authors: Deborah
authors: D
authors: Elstein
authors: Canadian Organization for Rare Disorders,Toronto.
authors: Durhane
authors: D
authors: Wong-Rieger
authors: McMaster University,Faculty of Health Sciences, Clinical Epidemiology and Biostatistics.
authors: Gordon
authors: G
authors: Guyatt
mesh_terms: D006304:Health Status; D006306:Health Surveys; D006801:Humans; D000071066:Patient Reported Outcome Measures; D011788:Quality of Life; D035583:Rare Diseases / Q000523:psychology*; D015203:Reproducibility of Results
keywords: Health technology assessment (HTA); Health-related quality of life (HRQoL); Minimally important difference (MID); Patient reported outcomes; Rare disease