Will a patient with lax criteria fall on the upper right or lower left of an ROC curve?

A patient with lax criteria would fall on the upper right of an ROC (Receiver Operating Characteristic) curve. This area of the curve represents a high sensitivity (true positive rate) and is indicative of a scenario where the criteria for a positive result are less stringent. In other words, the patient is likely to classify more cases as positive, possibly leading to more true positives along with an increased number of false positives.

In the context of the ROC curve, the upper right corner signifies a test that is highly sensitive, meaning that it successfully identifies most patients who truly have the condition (high true positive rate), while being less concerned about misclassifying some healthy individuals as positive (false positives). This scenario would correspond to a lax application of the criteria, as it implies a willingness to catch more cases—even at the risk of including some incorrectly.

The lower left area of the curve, in contrast, indicates low sensitivity and high specificity, where the criteria are strict, leading to potentially missed cases. The exact middle would reflect a balanced performance of sensitivity and specificity, while "none of the above" does not apply since the context clearly aligns with the upper right designation. Thus, the association between lax criteria and the upper right area of the ROC curve is direct