We cannot fully rule out influences of extra-pancreatic lipases on our lipase assay, but believe that this is of minor concern, as higher variation between lipase activity and fPLI seems to happen mainly in healthy cats with low values within RI [40] compared to very strong correlations between both lipase assays in cats with suspicion of pancreatitis [2,9,11]. Here, PNLIP is linked to pancreatitis.