The well designed Lancet study by Franz E Babl and colleagues¹ compares three rules used for neuroimaging in paediatric patients with head trauma. As authors of the PECARN rules,² we highlight several important points that require consideration. First, the three prediction rules compared were published in 2006, 2009, and 2010, before enrolment for the study by Babl and colleagues began. Therefore, the 10% CT rate noted by Babl and colleagues should be considered in that context, because CT ordering was likely to have been influenced by the rules.

中文翻译：

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儿童头部受伤的决定规则

精心设计的Lancet研究由Franz E Babl及其同事¹比较了用于颅脑外伤小儿神经影像学的三个规则。作为PECARN规则的作者^2，我们重点强调了一些需要考虑的重要点。首先，比较的三个预测规则分别于2006年，2009年和2010年发布，然后开始由Babl及其同事开始进行这项研究。因此，在这种情况下，应考虑Babl及其同事指出的10％的CT发生率，因为CT排序可能已受到规则的影响。