Table 2.

Alternative modeling scales for flexsurvspline, and equivalent distributions for m = 0 (with parameter definitions as in the R d functions referred to elsewhere in the paper).

Model	g(S(t, z))	In flexsurvspline	With m = 0
Proportional hazards	log(− log(S(t, z))) (log cumulative hazard)	scale = "hazard"	Weibull shape γ1, scale exp(−γ0/γ1)
Proportional odds	log(S(t, z)−1 − 1) (log cumulative odds)	scale = "odds"	Log-logistic shape γ1, scale exp(−γ0/γ1)
Normal / probit	Φ−1(S(t, z)) (inverse normal CDF, qnorm)	scale = "normal"	Log-normal meanlog − γ0/γ1, sdlog 1/γ1