图4. 列线图模型的DCA曲线 黑线代表所有极早产儿均未发生NEC，净获利为0；绿线代表所有极早产儿均发生NEC，净获利率为该反斜线的斜率；红线代表本模型的DCA曲线，高风险阈概率在绿线和红线之间（0.33~1.0）时本模型预测NEC发生是可行的，患儿净获利率高。.
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