Relationships Between the Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS), and Clinical/Polysomnographic Measures in a Community Sample Relationships Between the Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS), and Clinical/Polysomnographic Measures in a Community Sample Download Relationship Between Snoring Sound Intensity and Sleepiness in Patients with Obstructive Sleep Apnea Response to Johnson K, Johnson D. Letter to the Editor