While previous studies have associated excessive and/or short sleep durations with increased risks of death, researchers from Cleveland Clinic (Ohio, USA) reveal findings on how sleep duration af¬fects quality of life and depression. Charles Bae and colleagues analyzed records collected on 10,654 patients, mean age of about 52 years. A standardized questionnaire assessed quality of life, and a screening tool rated depression. People with a "normal" sleep duration of six to nine hours per night had higher self-reported scores for quality of life and lower scores for depression severity , as compared to as compared to short sleepers (less than 6 hours nightly) and long sleepers (more than 9 hours per night). Further, among patients who reported having perfect health, there were a higher percentage of normal sleepers, who also had significantly lower scores for depression severity compared to short and long sleepers with perfect health. The researchers conclude that: “Short and long sleepers have a lower quality of life and screen higher for depression.”