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 this review, 8 studies [2,17-23] addressed the practice and perception of Ramadan fasting and 15 studies [21-35] reported on the metabolic effects of Ramadan fasting on maternal health in healthy pregnant women.
Category: