[1] UT Southwestern Med Ctr, Dept Internal Med, 5323 Harry Hines Blvd, Dallas, TX 75390 USA
[2] UT Southwestern Med Ctr, Dept Clin Sci, Dallas, TX 75390 USA
[3] UT Southwestern Med Ctr, Hlth Sci Digital Lib & Learning Ctr, Dallas, TX 75390 USA
[4] Univ Calif San Diego, Dept Internal Med, La Jolla, CA 92093 USA