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:Another clinically important feature is the length of the MBs, sometimes referred as the width (Mohlenkamp et al. 2002; Ozbag et al. 2002; Ozbag and Kervancioglu 2004).
Category: