Table 1.

Summary statistics of Gage and IWPC pharmacogenetic and clinical dose-initiation predictions of maintenance dose versus observed maintenance dose among 719 COAG study participants who achieved maintenance dose, for all participants and by race.

	Pharmacogenetic-guided dosing			Clinically guided dosing
	All participants	Black	Nonblack	All participants	Black	Nonblack
Achieved maintenance dose, n	370	84	286	349	89	260
Gage dose-initiation algorithm *
Partial R2 †	0.48	0.21	0.52	0.27	0.33	0.17
Spearman rank correlation ‡	0.72	0.50	0.75	0.54	0.70	0.46
Mean absolute difference, mg/d §	1.3	1.6	1.2	1.5	1.4	1.6
Predicted – observed dose, % **
≥ 1 mg/d	25	39	20	29	28	30
Within 1 mg/d	53	38	57	42	48	39
≤ -1 mg/d	22	23	22	29	24	31
IWPC dose-initiation algorithm
Partial R2 †	0.47	0.17	0.52	0.30	0.31	0.22
Spearman rank correlation ‡	0.70	0.49	0.73	0.54	0.69	0.46
Mean absolute difference, mg/d §	1.3	1.6	1.3	1.5	1.4	1.6
Predicted – observed dose, % **
≥ 1 mg/d	21	30	19	23	24	23
Within 1 mg/d	51	40	54	41	40	41
≤ -1 mg/d	28	30	27	36	36	36

^*Results for Gage dose-initiation algorithm were presented in Table S6 of the Supplementary Appendix to Kimmel et al., 2013.¹¹

^†Partial R² calculated from multivariable linear regression models of observed versus predicted maintenance dose, adjusted for clinical center.

^‡Spearman rank correlation between predicted and observed maintenance dose.

^§Mean absolute difference between predicted and observed maintenance dose, in mg/day.

^**Difference between predicted and observed maintenance dose, categorized as ≥ 1 mg/day, within 1 mg/day, and ≤ -1 mg/day.