Interventions designed to improve health-related behavior will only be justified if they lead to greater improvements in clinically relevant outcomes. To determine the impact of the proposed health behavior interventions to increase CPAP adherence on treatment outcomes, Aim 2 will compare measures of daytime function following 3 months of CPAP treatment across the three groups. The results of Aim 2 will demonstrate whether improvements in CPAP adherence due to web-based feedback with or without a financial incentive result in greater improvements in clinical outcomes.