Figure 2

Predicted risk using the clinical model plus urine YKL-40 versus the clinical model alone. Each patient has a predicted risk for the outcome determined by their individual factors in the clinical (regression) model. Adding YKL-40 to the model results in a new predicted risk for each patient based on their YKL-40 value (above or below 5 ng/ml). For each patient, the predicted risk from the clinical model alone is plotted (horizontal axis) against the new predicted risk (vertical axis) after adding YKL-40 to the model. The dotted line represents no change in predicted risk (unity) after adding YKL-40. Changes in predicted risk can be considered appropriate or inappropriate based on the true outcome status. For example, in patients that ultimately developed the outcome (A), increasing predicted risk would be appropriate and decreasing predicted risk would be inappropriate. The opposite is true for patients that did not develop the outcome (B)–decreasing predicted risk would be appropriate and increasing predicted risk would be inappropriate. Darker symbols here indicate patients that were reclassified in the appropriate direction.