Related Variables

	napdy	Have you taken any naps today?	Sleep Monitoring/Polysomnography/Evening and Morning Survey
	longnaps	On average, how long are your naps?	Sleep Questionnaires/Sleep Habits
	nonaps	If yes, how often have you had to take daytime naps of 5 minutes or longer?	Sleep Questionnaires/Sleep Habits
	tothrslp	How many total hours of actual sleep do you get in a 24-hour period (including naps)	Sleep Questionnaires/Sleep Habits