134 Appendix Appendix 1. Receiver operating characteristic (ROC) curve for swallowing problems after treatment, using the linear mixed model The area under the curve (AUC) is 0.957. The AUC for the different timings of assessment is 0.946 (T0), 0.963 (M3), 0.940 (M6), 0.971 (M12), and 0.979 (M24). The AUC can vary between 0 and 1, where a value of 0 indicated that the model has no diagnostic power, and a value of 1 indicates that the model has a perfect diagnostic accuracy