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:Saczynski et al. (2006) examined this issue in more than 2,500 older Japanese American men who were followed since 1964 as part of the Honolulu Heart Program and the Honolulu-Asia Aging Study.
Category: