Table 3. Diagnostic performance of intravoxel incoherent motion magnetic resonance parameters in distinguishing human epidermal growth factor receptor 2 (HER2) positive gastric cancers from HER2 negative ones.

Parameters	Cut-off	Sensitivity	Specificity	AUC	P value
ADC	1.321	0.900	0.651	0.733	0.023†
D	1.123	0.800	0.721	0.762	0.011†
f	0.119	0.800	0.395	0.510	0.919
D*	52.352	0.500	0.860	0.670	0.097

Note: ADC, apparent diffusion coefficient; D, pure diffusion coefficient; f, perfusion related fraction; D*, pseudo diffusion coefficient; AUC, area under the receiver operating characteristic (ROC) curve. The cut-off values of ADC, D and D* are in unit of × 10⁻³ mm²/sec. ^†P < 0.05 with ROC analysis.