Design and evaluation of PROMIS® fatigue and cognitive function short forms customized for adults with primary sclerosing cholangitis.

PURPOSE: The goal of the Primary Sclerosing Cholangitis Symptom Assessment Project (PSC-SAP) is to develop reliable and valid PSC symptom measures for use in clinical trials. This article describes the process for customizing PROMIS® Fatigue and PROMIS® Cognitive Function short forms for adults with PSC. METHODS: Relevant items from the PROMIS item banks were selected by matching findings from concept elicitation interviews. Participants were purposively selected for cognitive interviews if they were symptomatic with PSC-related fatigue or cognitive impairment and met general eligibility for PSC clinical trials. Interviews were recorded, transcribed, and coded. The precision of these PROMIS short forms for PSC to capture fatigue and cognitive function at different levels was analyzed. RESULTS: Participants' (n = 22) open-ended descriptions of fatigue and cognitive impairment were consistent with prior concept elicitation interviews. From the 95-item PROMIS Fatigue item bank, 13 items were selected that directly aligned with fatigue concepts described during concept elicitation. Data from the cognitive interviews confirmed that both measures possessed strong content validity, with items perceived as clear, relevant, and comprehensive. The PROMIS Fatigue Short Form-PSC exceeded the 0.90 reliability threshold for T-scores between 36 and 79; the PROMIS Cognitive Function Short Form-PSC exceeded the 0.90 threshold between T-scores of approximately 22 and 60. CONCLUSION: This study demonstrated the strength of PROMIS item banks to design PROMIS Fatigue and Cognitive Function short forms for adults with PSC. Once the psychometric properties of the PROMIS short forms are confirmed, these measures may be used to evaluate symptoms in PSC research and clinical trials.