Table 4.

Multilevel models for exposure to obesity on misperception score by age

Model	Age 9 (n = 1049)				Age 13 (n = 1170)				Age 16 (n = 1144)
	β	s.e.	t	P	β	s.e.	t	P	β	s.e.	t	P
Base
Random effects
Between schools	0.068	0.023	–	–	0.034	0.014	–	–	0.024	0.010	–	–
Within schools	1.211	0.050	–	–	0.655	0.028	–	–	0.543	0.023	–	–
Fixed effects
Intercept	−0.398	0.044	−8.98	<0.0001	−0.940	0.033	−28.79	<0.0001	−0.738	0.029	−25.02	<.0001
Gender (boy = 1)	0.075	0.059	1.09	NS	0.111	0.052	2.00	<0.05	−0.132	0.049	−2.71	<.01
1
Parent BMI	−0.040	0.007	−5.75	<0.0001	−0.011	0.006	−1.97	<0.05	−0.016	0.005	−2.96	<0.01
2
Schoolmate BMI	−0.270	0.033	−8.11	<0.0001	−0.063	0.022	−2.91	<0.001	−0.117	0.030	−3.89	<0.0001
3
Parent BMI	−0.035	0.007	−5.23	<0.0001	−0.011	0.006	−1.92	NS	−0.015	0.005	−2.83	<0.01
Schoolmate BMI	−0.281	0.035	−7.99	<0.0001	−0.075	0.023	−3.28	<0.001	−0.113	0.035	−3.20	<0.001

Abbreviations: BMI, body mass index; NS, not significant. Model 3, Student level: misperception = β₀+β₁ (gender) +β₂ (parent BMI)+ ε₀. School-level: β₀ = γ₀₀+γ₀₁ (schoolmate BMI)+μ₀. β₁ = γ₁₀+γ₁₁ (schoolmate BMI). β₂ = γ_20.