[1] St Elizabeths Med Ctr, Div Pulm Crit Care & Sleep Med, 736 Cambridge St, Boston, MA 02135 USA
[2] Massachusetts Gen Hosp, Div Pulm & Crit Care Med, Boston, MA USA
[3] Brigham & Womens Hosp, Div Pulm & Crit Care Med, Boston, MA USA
[4] Duke Univ, Div Pulm Allergy & Crit Care Med, Durham, NC USA
[5] Univ Penn, Div Pulm Allergy & Crit Care, Philadelphia, PA USA
[6] Washington Univ, Div Pulm & Crit Care Med, St Louis, MO USA
[7] Univ Iowa, Div Pulm Crit Care & Occupat Med, Iowa City, IA USA
[8] Temple Univ, Dept Thorac Med & Surg, Lewis Katz Sch Med, Philadelphia, PA USA
[9] Cleveland Clin, Resp Inst, Cleveland, OH USA
[10] Boehringer Ingelheim Pharmaceut Inc, Ridgefield, CT USA
[11] ILD Collaborat, Boston, MA USA
[12] Tufts Univ, Tufts Clin & Translat Sci Inst, Boston, MA USA
[13] Tufts Med Ctr, Inst Clin Res & Hlth Policy Studies, Boston, MA USA