Table 3.

Comparing multiple linear regression models with food expenditures and diet cost predicting HEI 2015 (n=768)

	Unadjusted models				Adjusted Models
	Mean HEI per $100	(95% CI)		p-value	Mean HEI per $100	(95% CI)		p-value
Linear models
Food expenditures per capita ($/month)	1.20	0.71	1.70	<0.0001	0.09	−0.49	0.67	0.77
Diet cost per 2,000 kcal ($/2,000 kcal/month)	6.54	5.51	7.56	<0.0001	5.33	4.15	6.50	<0.0001
Curvilinear models
Diet cost per 2,000kcal ($/2,000kcal/month)	19.98	11.83	28.14	<0.0001	17.82	9.76	25.88	<0.0001
Diet cost per 2,000 kcal ($/2,000kcal/month) squared	−2.23	−3.54	−0.91	0.0009	−2.06	−3.35	−0.78	<0.002

Notes: food expenditures per capita equal the sum of self-reported at-home and away from home food expenditures divided by household size; diet cost was estimated from FFQ intake data, divided by calories, multiplied by 30 to create a monthly diet cost variable, and adjusted to $/2,000kcal; both food expenditures and diet cost variables were then divided by $100 to estimate the mean HEI per $100 increase in monthly spending; unadjusted models: two separate unadjusted models were conducted- one with food expenditures per capita as the primary independent variable and another with diet cost as the independent variable; adjusted models: two separate generalized linear regressions with robust standard errors adjusting for age, gender, race/ethnicity, marital status, education, property values, food assistance, and county were conducted - one including food expenditures as the primary independent variable, another with diet cost as the primary independent variable.