Figure 5: Figure 5 depicts the receiver operating characteristics (ROC) curves for the IC-2 of group average 7 for NTG patients (left) and POAG patients (right). If the values were aligned on the diagonal, this ability would be equal to chance. For a sensitivity and specificity of 100%, the ROC curve would follow the leftmost and the topmost margin of the graph. Thus, the area under the ROC curve is a measure of the ability of this parameter to differentiate between patients and controls. For NTG patients, the area under the ROC curve was 0.72 and for POAG it was 0.78, which is significantly better than chance (p=0.02).