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  5. Wheel and Spokes Diagram: Clinical Outcome Assessments (text version)
  1. Development & Approval Process (Drugs)

Wheel and Spokes Diagram: Clinical Outcome Assessments (text version)

Wheel and Spokes Diagram: Clinical Outcome Assessments (text version)

(PDF version - 1MB)

Spoke I:
Identify Context of Use (COU) and Concept of Interest (COI)

  • Outline hypothesized concepts and potential claims
  • Determine intended population
  • Determine intended application/characteristics (type of scores, mode and frequency of administration)
  • Perform literature/expert review
  • Develop hypothesized conceptual framework
  • Position COA within a preliminary endpoint model 
  • Document COU and COI


Spoke II: Draft Instrument and Evaluate Content Validity

  • Obtain patient or other reporter input
  • Generate new items 
  • Select recall period, response options and format
  • Select mode/method of administration/data collection
  • Conduct cognitive interviewing
  • Pilot test draft instrument
  • Finalize instrument content, format and scoring rule
  • Document content validity


Spoke III: Cross-sectional Evaluation of Other Measurement Properties

  • Assess score reliability (test-retest or inter-rater) and construct validity
  • Establish administration procedures & training materials
  • Document measure development
  • Prepare a user manual
  • Consider submitting to FDA for COA qualification for use in exploratory studies prior to longitudinal evaluation


Spoke IV: Longitudinal Evaluation of Measurement Properties/Interpretation Methods

  • Assess ability to detect change and construct validity 
  • Identify responder definition(s)
  • Provide guidelines for interpretation of treatment benefit and relationship to claim
  • Document all results
  • Update user manual
  • Submit to FDA for COA qualification as effectiveness endpoint to support claims


Spoke V: Modify Instrument

  • Identify a new COU
  • Change wording of items, response options, recall period, or mode/method of administration/data collection
  • Translate and culturally adapt 
  • Evaluate modifications using spokes I - IV
  • Document all changes
  • Consider submitting to FDA for qualification of new COA, as appropriate