LAUSR

between colectomized and comparators patients according to age at UC diagnosis, age at colectomy, year of colectomy and time between UC onset and colectomy. These results lead to the discussion as meth-odologicbiasescouldinfluencethesedivergentobservations.First,the absolute numbers of PSC diagnosis in sub ‐ analysis remained low despitenationalregistry.Second,theregistryspannedalargeperiodof time(from1990to2018)whichcaninfluencetheseresults.Ontheone hand,thediagnosticmethodofPSChaschangedovertimecoupledtoa greater awareness of this disease in IBD patients. 8 On the other hand, the therapeutic management of UC dramatically changed. 9 A last limit of this study is the lack of knowledge of the colectomy indication, which is a valuable information to improve the interpretation of results. Nonetheless, authors clearly mentioned these limits and the study remains of great value with regards to the available literature. In conclusion, Lundberg Ba ̊ ve et al. provided new insights on the risk of PSC by showing that colectomy does not impact the PSC onset in UC patients although sub analyses suggested that more granularity is needed in future studies. Overall, this epidemiologic observation is a newly valuable information to add in the understanding of this disease for whom the pathogenesis remains poorly understood.