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:Further, this similar profile has been described for aMCI patients with a higher risk of conversion to AD (Auriacombe et al., 2010; Grober, Lipton, Hall, & Crystal, 2000; Petersen, 2007; Sarazin et al., 2010).
Category: