Mintz ML, Yawn BP, Mannino DM, Donohue JF, Hanania NA, Grellet CA, Gilsenan AW, McLeod LD, Dalal AA, Raphiou IH, Prillaman BA, Crater GD, Cicale MJ, Mapel DW. Prevalence of airway obstruction assessed by lung function questionnaire. Mayo Clin Proc. 2011 May 1;86(5):375-81.