Table 2.

Regression Coefficients (Unstandardized) and P values for Association between Health Literacy (Coded as a Categorical Variable) and Baseline-Corrected Outcomes (ie, Outcome Value at Follow-up minus Outcome Value at Baseline) in an Unadjusted Model, and a Model Adjusting for Age, Education, and Social Risk

Effect of health literacy (categorical) on baseline-corrected outcomes	Unadjusted model				Adjusted model^*
	Coeff. With Respect to low HL		95% Confidence Interval	P value^†	Coeff.	95% Confidence Interval	P value^†
Clinical
HbA1c	HL Med	0.11	−0.54 to 0.77	0.73	0.09	−0.60 to 0.79	0.79
HbA1c	HL High	−0.18	−0.71 to 0.34	0.50	−0.25	−0.86 to 0.35	0.40
BMI	HL Med	0.01	−1.99 to 2.01	0.99	0.00	−2.11 to 2.12	0.99
BMI	HL High	0.15	−1.41 to 1.71	0.85	0.14	−1.64 to 1.92	0.87
Behavioral
Medication adherence	HL Med	0.25	−1.02 to 1.52	0.70	0.05	−1.29 to 1.40	0.94
Medication adherence	HL High	−0.17	−1.15 to 0.82	0.74	−0.23	−1.37 to 0.90	0.69
Exercise	HL Med	−0.68	−1.62 to 0.27	0.16	−0.74	−1.74 to 0.27	0.15
Exercise	HL High	−0.14	−0.87 to 0.59	0.70	−0.21	−1.05 to 0.62	0.62
Vegetable intake	HL Med	−0.09	−0.88 to 0.70	0.83	0.09	−0.75 to −0.93	0.83
Vegetable intake	HL High	−0.08	−0.70 to 0.54	0.80	0.27	−0.43 to 0.97	0.45
Fat intake	HL Med	0.46	−0.19 to 1.11	0.16	0.47	−0.22 to 1.16	0.20
Fat intake	HL High	0.32	−0.19 to 0.83	0.22	0.25	−0.33 to 0.83	0.40
Sweetened beverage intake	HL Med	0.26	−0.18 to 0.70	0.25	0.13	−0.33 to 0.60	0.58
Sweetened beverage intake	HL High	0.17	−0.17 to 0.51	0.33	−0.00	−0.39 to 0.39	0.99

Note. Performing this analysis with health literacy coded as an ordinal variable produced similar non-significant results in every case.
↵* In the adjusted model, based on a causal DAG (Figure 1), we included the following variables as predictors in the regression model: age, social risks, and education.
↵† Please note that the P values shown here are not adjusted for multiple comparisons because none have passed an unadjusted significance threshold.
Abbreviations: DAG, directed acyclic graph; HbA1c, hemoglobin A1c; BMI, body mass index; HL, health literacy.