Table 3.

Association between AUDIT-C change scores and change in VACS Index 2.0 score: Results of contrast tests^* for comparison of mean changes in VACS Index 2.0 between a priori- and post hoc- specified AUDIT-C change scores among n = 76,206 observations

Specified AUDIT-C change scores		Predicted change in VACS Index 2.0 Score Associated with Specified AUDIT-C Change Scores		p-value comparing predicted change in VACS Index 2.0 Score estimated for specified AUDIT-C Change Scores*
ΔA**	ΔA'**	ΔY (95% CI)	ΔY' (95% CI)
A priori contrasts to test hypothesis
0	−2	0.42 (0.31, 0.52)	0.46 (0.27, 0.65)	0.6704
0	−5	0.42 (0.31, 0.52)	−0.77 (−1.08, 0.47)	<0.001
−5	−8	−0.77 (−1.08, 0.47)	−2.05 (−2.62, −1.47)	<0.001
Post-hoc contrast tests to assess effects of decreases in drinking
0	+2	0.42 (0.31, 0.52)	0.31 (0.12, 0.50)	0.2939
0	+5	0.42 (0.31, 0.52)	0.04 (−0.23, 0.30)	0.0076
+1	−1	0.36 (0.21, 0.51)	0.60 (0.45, 0.75)	0.0140
+5	−5	0.04 (−0.23, 0.30)	−0.77 (−1.08, 0.47)	0.0001
+5	+8	0.04 (−0.23, 0.30)	−0.24 (−0.73, 0.26)	0.0444
+8	−8	−0.24 (−0.73, 0.26)	−2.05 (−2.62, −1.47)	<0.001

KEY: Above, mean change from initial to follow-up VACS Index 2.0 Score (ΔY) associated with one AUDIT-C change score (ΔA) are compared to mean changes in VACS Index 2.0 Score (ΔY') associated with another AUDIT-C change score (ΔA'); negative AUDIT-C change score indicates increased AUDIT-C; positive AUDIT-C change score indicates decreased AUDIT-C

^*p-value for contrast, tested using primary model (Block 2) adjusted for demographics, initial VACS Index Score 2.0, and days between measures.

^**N for AUDIT-C Δ −8 = 173; N for AUDIT-C Δ −5 = 408; N for AUDIT-D Δ −2 = 3,479; N for AUDIT-C Δ −1 = 9,157; N for AUDIT-C Δ 0 = 41,466; N for AUDIT-C Δ +1 = 9,963; N for AUDIT-C Δ +2 = 3,939; N for AUDIT-C Δ +5 = 510; N for AUDIT-C Δ +8 = 220.