Figure 8.

The ROC curves based on $T_{oral}$ imputed from $T_{max}$ and regression methods of constant offset, weighted linear and segmented linear for IRT-1. The triangle, circle and squre markers on curves show the Se/Sp values when $T_{cut}$ equals $T_{op.cut}$, $T_{p.op.cut}$, and $T_{thresh}$ respectively.