School of Medicine, University of Texas Medical Branch, Galveston, Texas 77555, USA.
Department of Preventive Medicine and Population Health, University of Texas Medical Branch, Galveston, Texas 77555, USA; Department of Orthopaedic Surgery and Rehabilitation, University of Texas Medical Branch, Galveston, Texas, 77555 USA.
Injury. 2021 Feb;52(2):147-153. doi: 10.1016/j.injury.2020.10.051. Epub 2020 Oct 10.
Traumatic brain injury (TBI) prognostic prediction models offer value to individualized treatment planning, systematic outcome assessments and clinical research design but require continuous external validation to ensure generalizability to different settings. The Corticosteroid Randomization After Significant Head Injury (CRASH) and International Mission on Prognosis and Analysis on Clinical Trials in TBI (IMPACT) models are widely available but lack robust assessments of performance in a current national sample of patients. The purpose of this study is to assess the performance of the CRASH-Basic and IMPACT-Core models in predicting in-hospital mortality using a nationwide retrospective cohort from the National Trauma Data Bank (NTDB).
The 2016 NTDB was used to analyze an adult cohort with moderate-severe TBI (Glasgow Coma Scale [GCS] ≤ 12, head Abbreviated Injury Scale of 2-6). Observed in-hospital mortality or discharge to hospice was compared to the CRASH-Basic and IMPACT-Core models' predicted probability of 14-day or 6-month mortality, respectively. Performance measures included discrimination (area under the receiver operating characteristic curve [AUC]) and calibration (calibration plots and Brier scores). Further sensitivity analysis included patients with GCS ≤ 14 and considered patients discharged to hospice to be alive at 14-days.
A total of 26,228 patients were included in this study. Both models demonstrated good ability in differentiating between patients who died and those who survived, with IMPACT demonstrating a marginally greater AUC (0.863; 95% CI: 0.858 - 0.867) than CRASH (0.858; 0.854 - 0.863); p < 0.001. On calibration, IMPACT overpredicted at lower scores and underpredicted at higher scores but had good calibration-in-the-large (indicating no systemic over/underprediction), while CRASH consistently underpredicted mortality. Brier scores were similar (0.152 for IMPACT, 0.162 for CRASH; p < 0.001). Both models showed slight improvement in performance when including patients with GCS ≤ 14.
Both CRASH-Basic and IMPACT-Core accurately predict in-hospital mortality following moderate-severe TBI, and IMPACT-Core performs well beyond its original GCS cut-off of 12, indicating potential utility for mild TBI (GCS 13-15). By demonstrating validity in the NTDB, these models appear generalizable to new data and offer value to current practice in diverse settings as well as to large-scale research design.
创伤性脑损伤（TBI）预后预测模型可为个体化治疗计划、系统的结果评估和临床试验设计提供价值，但需要不断进行外部验证，以确保在不同环境下的通用性。皮质类固醇随机分组后严重颅脑损伤（CRASH）和国际颅脑损伤预后分析与临床试验（IMPACT）模型广泛可用，但缺乏对当前全国性患者样本中性能的稳健评估。本研究的目的是使用国家创伤数据库（NTDB）中的全国性回顾性队列评估 CRASH-Basic 和 IMPACT-Core 模型预测住院死亡率的性能。
使用 2016 年 NTDB 分析格拉斯哥昏迷量表（GCS）≤12、头部简明损伤量表为 2-6 的中重度 TBI 成年患者队列。比较观察到的住院死亡率或出院到临终关怀与 CRASH-Basic 和 IMPACT-Core 模型分别预测的 14 天或 6 个月死亡率。性能指标包括区分度（接受者操作特征曲线下面积[AUC]）和校准（校准图和 Brier 评分）。进一步的敏感性分析包括 GCS≤14 的患者，并将出院到临终关怀的患者视为在 14 天内存活。
共有 26228 名患者纳入本研究。两种模型在区分死亡患者和存活患者方面均表现出良好的能力，IMPACT 显示出稍高的 AUC（0.863；95%CI：0.858-0.867），而 CRASH 为 0.858（0.854-0.863）；p<0.001。在校准方面，IMPACT 在较低分数时过度预测，在较高分数时预测不足，但大范围内校准良好（表明没有系统的过度/预测不足），而 CRASH 则一致低估死亡率。Brier 分数相似（IMPACT 为 0.152，CRASH 为 0.162；p<0.001）。当包括 GCS≤14 的患者时，两种模型的性能均略有提高。
CRASH-Basic 和 IMPACT-Core 均可准确预测中重度 TBI 后的住院死亡率，而 IMPACT-Core 超出了其原始 GCS 截止值 12，表明其对轻度 TBI（GCS 13-15）有潜在的应用价值。通过在 NTDB 中证明有效性，这些模型似乎可推广到新数据，并为不同环境下的当前实践以及大规模研究设计提供价值。
