Determination of cutoff value for a continuous variable using concordance type measure

Oregon Convention Center 

Identifying an optimal cutoff value of continuous variable associated with outcome variable is important for classifying high and low risk groups. This plays an important role in tailoring distinct treatment or procedure to each group. When outcome variable is the form of survival data with competing risk, methods for selecting cutoff value of continuous variable using test statistic have been proposed. Notably, even though concordance type measures have been commonly used to assess discriminatory power in survival data with competing risk, limited attention has been given to the determination of cutoff value for continuous variable using concordance type measure. This study proposed the methods for determining cutoff value of a continuous variable associated with survival outcome with competing risk using concordance type measures and evaluated the performances of the methods through simulation scenarios. These methods were also applied to real data to assess their practical utility. Simulation results indicated that the proposed methods tended to have good performance, even when the true cutoff value deviates from the center of the distribution of continuous variable.

Cutoff value of continuous variable

Survival outcome with competing risk

Concordance type measure 

Korean International Statistical Society