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:Asthma control was measured by the ACT, as previously described.(37) Self-reported healthcare seeking was elicited by asking participants how many times in the last year they had consulted HCPs regarding their asthma or needed to use emergency medical services due to their asthma (including being hospitalised, calling an ambulance, being sent to the hospital by their GP/asthma specialist doctor and staying overnight in hospital), and if they had, how many days their asthma had led them to be hospitalised in the last year.
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