question: How is asthma classified ?
answer: according to the frequency of symptoms , forced expiratory volume in one second ( FEV1 ) , and peak expiratory flow rate
turker_answer: Asthma is classified by the frequency of symptoms , forced expiratory volume in one second ( FEV1 ) , and peak expiratory flow rate .
rule-based: Asthma is classified by according to the frequency of symptoms , forced expiratory volume in one second ( FEV1 ) , and peak expiratory flow rate .