TABLE 3.

Adjusted Differences Between 2003 and 2006 Law Change Categories in Within-Student Change in BMI or Weight Status^a

Weight Measure	2003–2006 Lawb	βc	95% CI	P Value
BMI
	No change–weak	−0.32	−0.70, 0.05	.09
	No change–strong	−0.44	−0.71, −0.18	.002
	New laws–weak	−0.39	−0.56, −0.22	.001
	New laws–strong	−0.10	−0.33, 0.12	.36
	Weaker laws	−0.04	−0.24, 0.15	.66
Overweight
	No change–weak	−4.0	−9.8, 1.8	.17
	No change–strong	−3.6	−7.5, 0.3	.07
	New laws–weak	−4.5	−6.0, −3.0	.001
	New laws–strong	−2.8	−5.5, −0.2	.04
	Weaker laws	−3.2	−6.3, −0.1	.04
Obesity
	No change–weak	−1.2	−4.8, 2.5	.52
	No change–strong	−0.9	−3.4, 1.6	.46
	New laws–weak	−0.8	−2.7, 1.1	.40
	New laws–strong	0.0	−1.8, 2.0	.94
	Weaker laws	−0.4	−5.1, 4.3	.88

^aReferent: States with mean rating = 0 for elementary school laws in 2003 and middle school laws in 2006.

^bDifference between mean rating for state elementary school laws in 2003 and middle school laws in 2006. No change–weak: Equal mean rating (1–2). No change–strong: Equal mean rating (>2). New laws–weak: Mean higher for 2006 middle school laws (1–2). New laws–strong: Mean higher for 2006 middle school laws (>2). Weaker: Mean lower for 2006 middle school laws.

^cAbsolute difference in average within-student change in BMI or probability of overweight/obesity, based on fixed-effect model, adjusted for locale and SES.