Endpoint Selection

Endpoint Selection

Running CompARE

For each composite component, the user is prompted for the anticipation of:

CompARE computes the Assympotic Relative Efficiency1 (ARE), so that if the ARE is higher than 1, the use of the composite endpoint (CE) consiting of the union of both endpoints is recommended as the primary endpoint of the trial. If the ARE is lower than 1, the use of the Relevant endpoint is preferred over the CE as the primary endpoint of the trial.

Input Items

Output Items


Zodiac Trial compared the efficacy of the Vandetanib plus docetaxel versus docetaxel as second-line treatment in patients with advanced non-small-cell lung cancer. The main endpoint is the Progression Free Survival (PFS) composed by Overall Survival (OS, Endpoint 1) and the Objective Tumor Progression (OTP, Endpoint 2). The probabilities of observing each component in the control group were P01=0.59 and P02=0.74, respectively. The reported cause-specific HRs for each component were HR1=0.91 for the OS and HR2=0.77 for the OTP. The correlation between endpoints is not reported, but it is known than the HR for the Composite endpoint (PFS) is 0.79. Under this situation, if we assume constant hazards (Risk over time) for both endpoints, the use of PFS as composite endpoint is preferred. In fact, in any combination of hazards (increasing, decreasing or constant), the design with the PFS as the primary endpoint is mors efficient than the use of the Endpoint 1.


  1. Gomez G, Lagakos SW. Statistical considerations when using a composite endpoint for comparing treatment. 2013. Statistics in Medicine. 32(5):719-38. doi: 10.1002/sim.5547.