The asthma Symptom Free Days Questionnaire: how reliable are patient responses?
Yawn BP, Israel E, Wechsler ME, Pace W, Madison S, Manning B, Doros G, Fuhlbrigge A. The asthma Symptom Free Days Questionnaire: how reliable are patient responses? J Asthma. 2019 Nov; 56(11):1222-1230.