Abstract
A statistical study was made of reported night-waking in a national cohort of British 5-year-olds in order to explore long-term associations with physical, behavioural and mental development. After adjusting for the most likely confounders, reported night-waking at five was found to be linked at 10 years of age to certain chronic medical conditions and some symptoms of emotional distress. No convincing relationships existed between night-waking at five and selected measures of later physical development or intellectual ability.