Evaluate the collective function of references cited together in a given text segment.
Classify their combined role into one of the following categories: 'method', 'background', or 'result'.

Text:Spontaneous remission was defined as remission occurring in the absence of corticosteroid therapy, that is, disappearance of the pancreatic swelling visualized on CT and/or resolution of the diffuse narrowing of the main pancreatic duct as visualized by endoscopic retrograde cholangiopancreatography (ERCP) prior to the commencement of steroid therapy, as previously described [12].
Category: