[1] Univ Calif San Francisco, Sch Nursing, San Francisco, CA USA
[2] Univ Calif San Francisco, Sleep Disorders Ctr, San Francisco, CA USA
[3] SFVA Healthcare Syst, Dept Med, San Francisco, CA USA
[4] UCSF, Sleep Disorders Ctr, 2330 Post St,Suite 420, San Francisco, CA 94115 USA