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:Findings reported by Bryzgalova et al (194), suggesting reduced total GLUT4 levels in muscle as an underlying cause of the ER KO insulin resistance phenotype, were not supported by data from Ribas et al (192).
Category: