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:…dementia (VCID) is the second leading cause of dementia behind Alzheimer's disease, and is a frequent comorbidity in the Alzheimer's patient (Cooper and Mitchell 2016; Dichgans and Leys 2017; Greenberg et al. [for MarkVCID consortium] 2017; Kalaria 2016; Perrotta et al. 2016; Sudduth et al. 2017).
Category: