Fig. 4From: Switch of noninvasive ventilation (NIV) to continuous positive airway pressure (CPAP) in patients with obesity hypoventilation syndrome: a pilot studyChanges in ESS, PSQI and SRI scores one month after the switch to CPAP. Definition of abbreviations: NIV: Non Invasive Ventilation; CPAP: Continuous Positive Airway Pressure; ESS: Epworth Sleepiness Scale, PSQI: Pittsburgh Sleep Quality Index; SRI: Severe Respiratory Insufficiency questionnaire; NS: no significant difference; *: significant difference p < 0.05Back to article page