The Simple Cholestatic Complaints Score is a valid and quick patient-reported outcome measure in primary sclerosing cholangitis

Background: Measuring symptoms and disease burden in patients with primary sclerosing cholangitis (PSC) is increasingly important for daily practice and clinical trials. The Simple Cholestatic Complaints Score (SCCS) is a four-item questionnaire, that measures cholestatic symptoms (pruritus, fatigue, RUQ abdominal pain and fever) in PSC patients. The aim of this study was to evaluate reliability and validity of SCCS in a Dutch population. Methods: The study population consisted of 212 patients from the Dutch prospective PSC registry. Data were collected via digital surveys. Reliability was evaluated by internal consistency and reproducibility. Construct-, criterion- and discriminant validity were determined. The ability to detect clinical change with SCCS was evaluated in patients who underwent endoscopic intervention. Simple Cholestatic Complaints Score collected by email and by a mobile application were compared. Results: A total of 153 patients completed the questionnaire. Internal consistency was moderate and increased to 0.71 after removal of the fever item. Test-re-test reproducibility was high (intraclass correlation coefficient = 0.96). Criterion validity was good (all > 0.82). Construct validity was in line with a priori hypothesized correlations in 80%. SCCS was able to differentiate between clinically different groups. There was no difference between inflammatory bowel disease (IBD) and non-IBD patients. Simple Cholestatic Complaints Score was responsive to change after endoscopic intervention in successfully treated patients. Simple Cholestatic Complaints Score measurement by digital questionnaire and a mobile application was comparable. Conclusion: The SCCS is a valid instrument to measure cholestatic symptoms in PSC patients. Because of its quick and easy to use properties it is suitable for frequent monitoring of symptoms in clinical trials and daily practice.