Abbreviations: SD = standard deviation, IQR = interquartile range.
Significant P -values are bold.
1 Higher scores indicate more sleep problems
2 Compared to norm population (mean=50, SD=10)
3 Compared to percentage of moderate sleep problems in
the norm population (20%)
4 Compared to percentage of severe sleep problems in
the norm population (5%)
5 Compared to percentage of sleep problems (moderate
or severe) in the norm population (25%)