[1] CE Outcomes LLC, Birmingham, AL 35226 USA
[2] Northwestern Univ, Asthma COPD Program, Div Pulm & Crit Care Med, Feinberg Sch Med, Chicago, IL 60611 USA
[3] Columbia Univ, Coll Phys & Surg, Dept Med, Div Pulm, New York, NY USA
[4] Boehringer Ingelheim Pharmaceut Inc, Ridgefield, CT 06877 USA
[5] COPD Fdn, Miami, FL USA