[1] UT Southwestern Med Ctr, Dept Internal Med, Dallas, TX 75390 USA
[2] Parkland Mem Hosp & Affiliated Inst, Div Hosp Med, Dallas, TX 75235 USA
[3] Univ Texas Hlth Sci Ctr Houston, Sch Publ Hlth, Dallas Reg Campus, Dallas, TX USA
[4] Childrens Hlth Syst Texas, Ctr Pediat Populat Hlth, Dallas, TX USA
[5] Univ Texas Dallas, Hlth Sci Ctr, Dallas, TX USA
[6] Cedar Sinai Med Ctr, Div Pulm & Crit Care Med, Dept Internal Med, Womens Guild Lung Inst, Los Angeles, CA USA
[7] UT Southwestern Med Ctr, Div Digest & Liver Dis, Dept Internal Med, Dallas, TX USA
[8] UT Southwestern Med Ctr, Div Pulm Crit Care, Dallas, TX USA