The University of Pittsburgh was awarded a $100,541.00 Project Grant (R01HL170675) under the National Institutes of Health (NIH) Trans-NIH Research Support program (CFDA 93.310) to assess the night-to-night variability in novel obstructive sleep apnea (OSA) severity metrics and their impact on day-to-day sleepiness, fatigue, mood, and stress. The 4-year research project will leverage cutting-edge sleep monitoring technology and ecological momentary assessments to characterize reliable biomarkers of OSA disease severity, with a focus on understanding sex and gender-related differences in OSA presentation and associated functional impairments. The study aims to create a new paradigm in OSA research that will lead to improved diagnosis and management of the condition, particularly for women who may be underdiagnosed using current diagnostic criteria.