[1] PAMPAs Fed Univ, Bage, RS, Brazil
[2] Pediat Asthma Prevent Program PIPA, Uruguayana, Brazil
[3] Univ Toronto, Inst Hlth Policy Management & Evaluat, Dalla Lana Sch Publ Hlth, Toronto, ON, Canada
[4] Hosp Sick Children, Child Hlth Evaluat Sci, Toronto, ON, Canada
[5] Univ Fed Bahia, Ctr Excellence Asthma, Salvador, BA, Brazil
[6] Univ Fed Sao Paulo, Escola Paulista Med, Dept Pediat, Div Allergy Clin Immunol & Rheumatol, Sao Paulo, Brazil