Items in the single-score PROMIS Fatigue Short Forms (SFs) demonstrate content validity and can adequately capture the wide range of fatigue experiences of people with rheumatoid arthritis (RA), a recent study found. Researchers recruited people with RA from an online patient community (n=200) and 3 academic medical centers (n=84) in the US. Participants completed both SFs then rated the comprehensiveness and comprehensibility of the items to their fatigue experience. Researchers found:

• Mean SF scores were similar among clinic patients reflecting mild fatigue (ie, 54.5–55.9), but were significantly higher in online participants.
• SF Fatigue scores correlated highly (r ≥ 0.82) and moderately with patient assessments of disease activity (r ≥ 0.62).
• Most (70–92%) reported that the items “completely” or “mostly” reflected their experience.
• Almost all (≥ 94%) could distinguish general fatigue from RA fatigue.
• Most (≥ 85%) rated individual items questions as “somewhat” or “very relevant” to their fatigue experience, averaged their fatigue over the past 7 days (58%), and rated fatigue impact vs severity (72 vs 19%).
• 99% rated fatigue as an important symptom they considered when deciding how well their current treatment was controlling their RA.