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:Previous work has shown that such measures are related to dual tasking measures of gait variability (Springer et al. 2006; Yogev et al. 2005) and that they respond as expected to cognitive-enhancing pharmacologic therapy (Auriel et al.
Category: