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:The significantly better survival in younger patients in our study is in accordance with previous results [8, 9, 12, 13, 15, 19, 20, 23, 24, 25, 30, 31, 33, 34].
Category: