Fig. 2From: The interpretation of change score of the pain disability index after vocational rehabilitation is baseline dependentROC curves of the PDI total sample and baseline quartiles. ROC, receiver operating characteristic; PDI, Pain Disability Index; Q, quartile; AUC, area under the curve. a ROC-curve of total study sample (n = 341). b ROC-curve of the sample with PDI baseline quartile 1 score (n = 89). c ROC-curve of the sample with PDI baseline quartile 12 score (n = 81). d ROC-curve of the sample with PDI baseline quartile 13 score (n = 83). e ROC-curve of the sample with PDI baseline quartile 14 score (n = 88)Back to article page