n = 226

Sleep quality (points)

Watching TV (hour)

Using internet (hour)

Playing game (hour)

Length of sleep (hour)

Age (years)

Body temperature

0.03^n.s.

0.07^n.s.

−0.01^n.s.

−0.11^n.s.

0.04^n.s.

−0.17*

Sleep quality

-

0.13*

0.03^n.s.

0.12^n.s.

−0.10^n.s.

−0.07^n.s.

Watching TV

-

−0.02^n.s.

0.22**

−0.28***

0.08^n.s.

Using internet

-

0.25***

−0.15*

0.30***

Playing game

-

−0.18**

0.13*

Length of sleep

-

-0.37***