[Incidence and persistence of problems at sleep onset and sleep continuation in the preschool period: results of a prospective study of a representative sample in Bavaria].

The prevalence and persistence of sleeping problems was studied in a prospective investigation of a representative sample of 432 German children at the ages of 5, 20 and 56 months. 21.5% of children had night waking problems at 5 months, 21.8% at 20 months and 13.3% at 56 months. Falling asleep difficulties were diagnosed in 12.1% of 4-5 year olds. One in four of five year-olds slept regularly in the bed with the parents (co-sleeping). Children with night waking problems had a 2.2 to 2.5 fold increased risk to remain nightwakers from one assessment point to the next compared with non-wakers. 7 to 14% of parents were distressed by their children's sleeping behaviour. Parental behaviour often contributed to continued sleeping problems because the children were not supported in acquiring appropriate skills to settle to sleep unaided. A developmental model for the treatment of sleeping problems is discussed.