Fig. 3

Receiver operating characteristics curves for the top performing models. The ten-fold cross validation with standard deviation (SD) is depicted as the blue line (mean) and shaded gray area (± 1SD). The dark maroon line represents the test set ROC curve. The test set performance was faithful to the training set. The dotted black line represents AUC for classification by chance given a random and equal distribution of headache data. ROC = receiver operating characteristics; AUC = area under the curve