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:…were: (1) Enlarged ventricles out of proportion to sulcal atrophy on computed tomography or magnetic resonance imaging (Evan’s index of at least 0.3; Shprecher et al., 2008), (2) Gait disturbance with either urinary incontinence and/or cognitive impairment, (3) No evidence of a known cause for…
Category: