[1] Mayo Clin, Dept Med, Pulm Crit Care, Rochester, MN USA
[2] Mayo Clin, Dept Quantitat Hlth Sci, Clin Trials & Biostat, Rochester, MN USA
[3] Mayo Clin, Dept Quantitat Hlth Sci, Epidemiol, Rochester, MN USA
[4] Mayo Clin, Dept Pediat & Adolescent Med, Community Pediat & Adolescent Med, Rochester, MN USA
[5] Mayo Clin, Dept Quantitat Hlth Sci, Rochester, MN USA
[6] Mayo Clin, Dept Pediat & Adolescent Med, Rochester, MN USA