<qa>  What is the cause of sleep quality in Taiwanese hemodialysis patients?Sleep quality is an important predictor of healthy status,quality of life and life span. Sleeping problems affect 5080 in hemodialysis patients. Sleep quality and related factors research in hemodialysis patients has been discussed and studied globally. Previous studies show insomnia, excessive daytime sleepinessEDS, sleep apnea syndromeSAS, restless legs syndromeRLS are major causes of poor sleep quality . There is few data to show the influential factors related to sleep quality in Taiwanese hemodialysis patients. 