[Discriminative properties and validity of a health status questionnaire in obstructive airway disease patients: the Airway Questionnaire 20].

Objective: To evaluate the discriminative properties and validity of the Airways Questionnaire 20 (AQ20) in a sample of patients with airway obstruction and to compare its properties with those of the St George's Respiratory Questionnaire (SGRQ) and the Short Form 36 (SF-36).

Patients And Methods: A convenience sample of 47 subjects was recruited from among 61 consecutive patients referred to an outpatient clinic specialized in obstructive airway diseases. All subjects completed the AQ20, SGRQ, and SF-36.