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:…logistic regression analyses, and those factors had previously been found to be associated with children vaccination coverage in the United States (Luman et al., 2004; Santibanez et al., 2006; Zhao and Luman, 2010): children race/ethnicity (non-Hispanic white only, non-Hispanic black only,…
Category: