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:In school-age children with CP, other researchers have found behavioral problems including passivity, immaturity, and anxiety (Graham & Rutter, 1968b; Haslett, 1978; Hourcade & Parette, 1984; Rosenbloom, 1971).
Category: