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:Construct validity of the CORE as a measure of melancholia Vares et al. (2015) investigated the underlying dimensions of depression comparing instruments that measure depression from different perspectives – namely, a self-report symptomatic scale (Beck Depression Inventory), a clinician-rated scale (Hamilton Depression Rating Scale) and the CORE measure of PMD, in a Brazilian sample.
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