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:Hearing loss and tinnitus have been linked, both pathophysiologically (Eggermont and Roberts, 2004; Jastreboff, 1990) and clinically (De Ridder et al., 2015a; Norena et al., 2002; Schecklmann et al., 2012b).
Category: