Sleep habits in Swedish children and adolescents: a longitudinal study

Introduction
Sleep length recommendations for Swedish school-aged children and adolescents are 9-11 h
for children aged 6-13 years and 8-10 h for adolescents aged 14-17 years. The aim was to
investigate sleep length in school-aged children and adolescents from 6 to 16 years in a
longitudinal study, and to investigate if shorter sleep length than recommended was
associated with experience of being tired at school.

Materials and Methods
A survey was distributed to the students at 4 time points, at age 6 (n=560), 10 (n=1253), 14
(n=1489) and 16 (n=1449) in a municipality in southern Sweden. At the age of 6, the
guardians responded to the survey, and at the other time points, the survey was completed
by the students.

Results
The mean sleep duration decreased during the period. At age 6, the mean sleep duration
was 10.2 h (SD .64), at age 10 the mean sleep duration was 9.5 h (SD .63), at age 14 the mean
sleep duration was 8.1 h (SD .98) and at age 16 the mean sleep duration was 7.1 h (SD 1.0).
Sleeping less than recommended was associated with being tired at school (p < .05).

Conclusions
The younger age group achieved the recommended sleep length, however, the oldest age
group, at 16 years, they slept less than recommended. Sleeping shorter than recommended
was associated with being tired at school.