Table 3.

Estimation of Interaction SADT Effects

	Two-Stage Method			Seq. Strat. (10-NN)
Interaction	Hazard Ratio	95% CI	p*	Hazard Ratio	95% CI	p*
Time of SADT (after radiation therapy)
0–2.5 years	0.26	(0.16, 0.42)	0.41	0.30	(0.18, 0.50)	0.76
2.5–4 years	0.16	(0.09, 0.26)		0.24	(0.13, 0.46)
4–6 years	0.27	(0.15, 0.47)		0.28	(0.14, 0.54)
6+ years	0.33	(0.15, 0.75)		0.47	(0.17, 1.30)
Age (at time of SADT)
≤ 71 years	0.22	(0.13, 0.37)	0.33	0.30	(0.16, 0.55)	0.31
71–76 years	0.23	(0.13, 0.43)		0.19	(0.09, 0.39)
76–80 years	0.18	(0.10, 0.33)		0.25	(0.13, 0.48)
80+ years	0.36	(0.21, 0.62)		0.44	(0.24, 0.79)
Predicted PSA† (at time of SADT)
≤ 1.5	0.20	(0.09, 0.46)	0.36	0.37	(0.16, 0.86)	0.51
1.5–2	0.14	(0.06, 0.31)		0.22	(0.09, 0.53)
2–3	0.31	(0.19, 0.48)		0.36	(0.22, 0.61)
3+	0.24	(0.15, 0.40)		0.23	(0.13, 0.39)
Predicted Slope of PSA† (at time of SADT)
≤ 0.4	0.65	(0.31, 1.35)	0.04	0.94	(0.41, 2.15)	0.02
0.4–0.7	0.27	(0.15, 0.49)		0.35	(0.17, 0.70)
0.7–1	0.21	(0.12, 0.37)		0.17	(0.08, 0.36)
1+	0.19	(0.12, 0.30)		0.26	(0.16, 0.41)
Predicted PSA, Slope of PSA† (at time of SADT)
PSA ≤ 2, Slope ≤ 0.7	0.30	(0.15, 0.60)	0.06	0.49	(0.22, 1.07)	0.10
PSA > 2, Slope ≤ 0.7	0.41	(0.22, 0.78)		0.47	(0.22, 0.98)
PSA ≤ 2, Slope > 0.7	0.07	(0.02, 0.22)		0.13	(0.05, 0.34)
PSA > 2, Slope > 0.7	0.24	(0.16, 0.37)		0.25	(0.16, 0.39)
Time (after SADT)
0–1.5 years	0.31	(0.20, 0.47)	0.14	0.37	(0.24, 0.55)	0.18
1.5–3 years	0.20	(0.11, 0.35)		0.19	(0.11, 0.33)
3–5 years	0.12	(0.06, 0.27)		0.24	(0.07, 0.81)
5+ years	0.28	(0.13, 0.59)		0.66	(0.11, 4.12)

^*P-value for Wald test of equal interaction effects

^†Predicted PSA and slope of PSA are based on log(PSA + 0.1)