The standard multiple regression analysis revealed that postoperative pain, fatigue, anxiety, and disturbances from environment of care could explain 59.4% of variance of quality of sleep (R2 = 0.594, F (4, 77) = 28.22, p < 0.001). The best predictor of quality of sleep was disturbances from environment of care (β = - 0.35, p < 0.001).