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:SM/J and LG/J differ in their phenotypic response to a high-fat diet, with SM/J being more responsive than LG/J for many obesity, diabetes-related, and serum lipid level traits [23,24].
Category: