Table 5.

Regression Coefficients (Fixed Effects), Random Effects, and P-values From Multivariate HLM Models That Include Individual-level Characteristics and Neighborhood SES As Explanatory Variables For Fruit/Vegetable Intake and Test the Interaction of Race/Ethnicity with Neighborhood SES, Using the Third National Health and Nutrition Examination Survey 1988-1994 (NHANES III) ¹

	Servings of Fruit and Vegetables Combined3 (n=13,281)		Servings of Fruit (n=13,310)		Servings of Vegetables (n=13,296)
NSES Effect by Race/Ethnicity2	Coeff	P-value	Coeff	P-value	Coeff	P-value
NSES for Mexican Am	0.18	0.0040	0.08	0.0346	0.09	0.0878
NSES for NH Black	0.13	0.0283	0.08	0.0423	0.05	0.2334
NSES for ‘Other’	0.35	0.0485	0.12	0.2311	0.23	0.1054
NSES for NH White	0.35	<0.0001	0.19	0.0004	0.14	0.0198
Random Effects
Level 1 variance	9.62	<0.0001	3.32	<0.0001	5.58	<0.0001
Level 2 variance	1.98	<0.0001	0.55	<0.0001	1.09	<0.0001
Level 3 variance	0.06	0.0599	0.04	0.0072	0.03	0.0704
ICC-level 2 (%) 4	16.96		13.95		16.28
ICC-level 3 (%) 4	0.53		1.06		0.44
Fit Statistics
-2 Res LL	77877.0		63759.1		70687.7
AIC	77883.0		63765.1		70693.7

¹Hierarchical linear models (HLM), or multi-level regressions, were conducted with PROC MIXED using SAS version 9.1. Level 1=individual level, level 2= tract level within counties, and level 3=county level. All models are adjusted for age, age-squared, gender, nativity, educational attainment, family income, employment status, and region of residence and include race/ethnicity, NSES, and NSES*race/ethnicity. Complete results are available from the authors.

²We used the Estimate statement within PROC MIXED models to directly estimate the effect of NSES for each racial/ethnic group (NSES+NSES*Race/Ethnicity) and test whether each effect is significantly different from zero.

³The effect of NSES on combined fruit and vegetable intake for Whites is significantly different from that for Mexican-Americans (P=0.03) and Blacks (P=0.01). There was no significant difference relative to Whites in the effect of NSES on fruit intake or vegetable intake for Mexican-Americans or Blacks. Furthermore, there was no significant difference between Blacks and Mexican-Americans in the effect of NSES on any of the dietary outcomes.

⁴ICCs = intra-class correlation coefficients, which provide an estimate of the proportion of total variance in dietary outcome that occurs between geographic areas. Level 2 ICCs provide an estimate of the proportion of variance in dietary outcome that occurs between tracts within counties while level 3 ICCs provide an estimate of the proportion of variance in dietary outcome that occurs between counties.