Introduction External cause of injury matrices is used to classify mechanisms/causes of injuries for surveillance and research. Little is known about the performance of the Centers for Disease Control and Prevention’s new external cause of injury matrix for Clinical Modification of the 10th Revision of the International Classification of Diseases (ICD-10-CM), compared with the ICD-9-CM version. Methods Dually coded (ICD-9-CM and ICD-10-CM) administrative data were obtained from two major academic trauma centres. Injury-related cases were identified and categorised by mechanism/cause and manner/intent. Comparability ratios (CR) were used to estimate the net impact of changing from ICD-9-CM to ICD-10-CM on the number of cases classified to each mechanism/cause category. Chamberlain’s percent positive agreements (PPA) were calculated and McNemar’s test was used to assess the significance of observed classification differences. Results Of 4832 and 5211 dual-coded records from the two centres, 632 and 520 with injury-related principal diagnoses and external cause codes in both ICD-9-CM and ICD-10-CM were identified. CRs for the mechanisms/causes with at least 20 records ranged from 0.85 to 1.9 at one centre and from 0.97 to 1.07 at the other. Among these mechanisms/causes, PPAs ranged from 33% for ‘other transport’ to 94% for poisoning at one centre, and from 75% for ‘other transport’ to 100% for fires/burns at the other centre. Case assignment differed significantly for falls, motor vehicle traffic, other transport, and ‘struck by/against’ injuries at one centre, and for ‘other pedal cyclist’ at the other centre. Conclusion Switching to ICD-10-CM and the new external cause of injury matrix may affect injury surveillance and research, especially for certain mechanisms/causes.

中文翻译：

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探索新的 ICD-10-CM 分类系统对伤害监测的影响：对两个医疗中心的双重编码数据进行分析

简介 损伤外部原因矩阵用于对损伤机制/原因进行分类，以供监测和研究。与 ICD-9-CM 版本相比，美国疾病控制与预防中心针对国际疾病分类第十版修订版临床修订版 (ICD-10-CM) 的新外伤原因矩阵的性能知之甚少。方法 从两个主要学术创伤中心获得双重编码（ICD-9-CM 和 ICD-10-CM）管理数据。与伤害相关的案件按机制/原因和方式/意图进行识别和分类。可比性 (CR) 用于估计从 ICD-9-CM 更改为 ICD-10-CM 对分类到每个机制/原因类别的病例数量的净影响。计算张伯伦阳性一致性百分比 (PPA)，并使用麦克尼马尔检验来评估观察到的分类差异的显着性。结果 在来自两个中心的 4832 份和 5211 份双编码记录中，识别出 ICD-9-CM 和 ICD-10-CM 中的 632 份和 520 份具有与伤害相关的主要诊断和外因代码。至少有 20 条记录的机制/原因的 CR 在一个中心为 0.85 至 1.9，在另一中心为 0.97 至 1.07。在这些机制/原因中，PPA 范围从一个中心“其他运输”的 33% 到中毒的 94%，以及另一个中心“其他运输”的 75% 到火灾/烧伤的 100%。一个中心的跌倒、机动车交通、其他交通和“被/撞”伤害的案例分配与另一中心的“其他踏板骑车人”的案例分配存在显着差异。结论 改用 ICD-10-CM 和新的损伤外因矩阵可能会影响损伤监测和研究，尤其是某些机制/原因。