More than a third of Americans don't get enough sleep. Are you one of them? How well do you really sleep at night?
It's not just about the number of hours. If you find yourself waking up in the middle of the night, or if your sleep problems spill into other areas of your life, you probably still have room for improvement.
For one useful, science-backed estimate of your sleep quality, try this questionnaire, called the Sleep Condition Indicator. It was developed by Colin Espie, a professor of sleep medicine at the University of Oxford.