TABLE II.

Usual sleep (hours/night), reported in 2001, and its estimated association (β, se) with BMI change (kg/m²) from 2000 to 2001. Models of categorical sleep time appear in middle five columns, and continuous sleep models are on right. Models adjust for age, age², menarche (2000–2001), height growth (2000–2001), and 2000 BMI.

Categories of Sleep						Continuous Sleep
	<=5 hrs	6 hours	7 hours	8 hours (referent)	9+ hours	β (se) (kg/m2 per hr/night)
Adjust for:
Internet, Coffee, Alcohol	+.133#	+.059	−.025	0	−.028	−.034*
	(.076)	(.046)	(.039)		(.073)	(.017)
Further adjust for:
Past Year Phys Act, TV/videos,Games	+.140#	+.061	−.020	0	−.023	−.034*
	(.075)	(.047)	(.039)		(.073)	(.016)
Only Girls Aged 18+
(height growth and menarche omitted)	+.322**	−.021	−.049	0	−.134	−.076**
	(.112)	(.076)	(.067)		(.121)	(.026)

^#0.05<P<0.10

^*P<0.05

^**P<0.01