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:In contrast, in other studies, DFI media has been reported to have lower specificity due to occurrence of non-Cronobacter strains with α-glycosidase activity (Cawthorn et al. 2008; Iversen et al. 2004).
Category: