Assessing the content validity of a Patient Reported Outcome Measure item pool for Rheumatoid Arthritis Disease...

Area of Science:

• Rheumatology and Health Outcomes Research
• Psychometrics and Measurement Science
• Patient-Reported Outcome Measures (PROMs)

Background:

• Assessing rheumatoid arthritis (RA) disease activity is crucial for effective patient management.
• Existing measures may require refinement to accurately capture the multifaceted nature of RA.
• A 12-item pool was developed based on Rasch measurement theory to assess RA disease activity.

Purpose of the Study:

• To evaluate the content validity of a 12-item item pool designed to measure rheumatoid arthritis (RA) disease activity.
• To determine if the item pool is relevant, comprehensive, and comprehensible to patients with RA.
• To gather patient perspectives on specific symptoms and their relationship to overall RA disease activity.

Main Methods:

• Cognitive interviews utilizing the 'think aloud' technique were conducted with 20 participants.
• Participants responded to the 12-item pool and additional relevant items.
• Reflexive thematic analysis and content analysis were used to assess content validity aspects.

Main Results:

• No concerns were raised regarding the comprehensiveness, comprehensibility, or relevance of the 12-item pool.
• Participants showed a lack of consensus on distinguishing RA symptoms from other conditions and on assessing tenderness and swelling.
• The majority felt fatigue and general health are not specific to RA disease activity.

Conclusions:

• The 12-item pool demonstrates adequate content validity for assessing rheumatoid arthritis (RA) disease activity.
• No additional items are currently required for this specific RA disease activity construct.
• Future research will be necessary to establish content validity for any new RA disease activity items.