Establishment and Validation of a Predictive Model for Radiation-Associated Aspiration Pneumonia in Patients with Radiation-Induced Dysphagia after Nasopharyngeal Carcinoma

Figure 4

DCA of the nomogram. Decision curves for PFS at (a) 1 year and (b) 3 years in the training cohort, at (c) 1 year and (d) 3 years in the internal validation cohort, and at (e) 1 year and (f) 3 years in the external validation cohort were applied to the nomogram. The -axis represents the threshold probability. The -axis measures the net benefit. The black line depicts the net benefit of the strategy of treating no patients. The blue line depicts the net benefit of the strategy of treating all patients. The red line represents the nomogram. The net benefit was calculated by subtracting the proportion of all patients who are false positive from the proportion who are true positive, weighting by the relative harm of forgoing treatment compared with the negative consequences of an unnecessary treatment. The threshold probability is where the expected benefit of treatment is equal to the expected benefit of avoiding treatment. For example, if the possibility of RAP development in a patient is over the threshold probability, then, a RAP treatment strategy should be adopted. Abbreviations: DCA: decision curve analysis; PFS: pneumonia-free survival; RAP: radiation-induced aspiration pneumonia.

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