Background Administrative data are frequently used in stroke research. Ensuring accurate identification of patients who had an ischaemic stroke, and those receiving thrombolysis and endovascular thrombectomy (EVT) is critical to ensure representativeness and generalisability. We examined differences in patient samples based on mode of identification, and propose a strategy for future patient and procedure identification in large administrative databases. Methods We used non-public administrative data from the state of California to identify all patients who had an ischaemic stroke discharged from an emergency department (ED) or inpatient hospitalisation from 2010 to 2017 based on International Classification of Disease (ICD-9) (2010–2015), ICD-10 (2015–2017) and Medicare Severity-Diagnosis-related Group (MS-DRG) discharge codes. We identified patients with interhospital transfers, patients receiving thrombolytics and patients treated with EVT based on ICD, Current Procedural Terminology (CPT) and MS-DRG codes. We determined what proportion of these transfers and procedures would have been identified with ICD versus MS-DRG discharge codes. Results Of 365 099 ischaemic stroke encounters, most (87.70%) had both a stroke-related ICD-9 or ICD-10 code and stroke-related MS-DRG code; 12.28% had only an ICD-9 or ICD-10 code and 0.02% had only an MS-DRG code. Nearly all transfers (99.99%) were identified using ICD codes. We identified 32 433 thrombolytic-treated patients (8.9% of total) using ICD, CPT and MS-DRG codes; the combination of ICD and CPT codes identified nearly all (98%). We identified 7691 patients treated with EVT (2.1% of total) using ICD and MS-DRG codes; both MS-DRG and ICD-9/ICD-10 codes were necessary because ICD codes alone missed 13.2% of EVTs. CPT codes only pertain to outpatient/ED patients and are not useful for EVT identification. Conclusions ICD-9/ICD-10 diagnosis codes capture nearly all ischaemic stroke encounters and transfers, while the combination of ICD-9/ICD-10 and CPT codes are adequate for identifying thrombolytic treatment in administrative datasets. However, MS-DRG codes are necessary in addition to ICD codes for identifying EVT, likely due to favourable reimbursement for EVT-related MS-DRG codes incentivising accurate coding. Data may be obtained from a third party and are not publicly available. This study used non-public data maintained by the California Office of Statewide Health Planning and Development. All data requests should be made directly to this organisation.

中文翻译：

---

在大型管理数据库中可靠识别缺血性中风、溶栓剂和血栓切除术的策略

背景 管理数据经常用于中风研究。确保准确识别缺血性卒中患者以及接受溶栓和血管内血栓切除术 (EVT) 的患者对于确保代表性和普遍性至关重要。我们根据识别模式检查了患者样本的差异，并提出了未来在大型管理数据库中识别患者和程序的策略。方法 我们使用来自加利福尼亚州的非公开行政数据，根据国际疾病分类 (ICD-9) (2010) 确定 2010 年至 2017 年从急诊科 (ED) 出院或住院的所有缺血性卒中患者–2015)、ICD-10 (2015–2017) 和医疗保险严重性诊断相关组 (MS-DRG) 出院代码。我们根据 ICD、当前程序术语 (CPT) 和 MS-DRG 代码确定了医院间转移的患者、接受溶栓剂的患者和接受 EVT 治疗的患者。我们确定了使用 ICD 和 MS-DRG 放电代码识别这些转移和程序的比例。结果 在 365 099 例缺血性卒中患者中，大多数（87.70%）同时具有卒中相关 ICD-9 或 ICD-10 编码和卒中相关 MS-DRG 编码；12.28% 只有 ICD-9 或 ICD-10 代码，0.02% 只有 MS-DRG 代码。几乎所有转账 (99.99%) 都是使用 ICD 代码识别的。我们使用 ICD、CPT 和 MS-DRG 代码确定了 32 433 名接受溶栓治疗的患者（占总数的 8.9%）；ICD 和 CPT 代码的组合几乎可以识别所有 (98%)。我们使用 ICD 和 MS-DRG 代码确定了 7691 名接受 EVT 治疗的患者（占总数的 2.1%）；MS-DRG 和 ICD-9/ICD-10 代码都是必要的，因为仅 ICD 代码就漏掉了 13.2% 的 EVT。CPT 代码仅适用于门诊/急诊患者，对 EVT 识别无用。结论 ICD-9/ICD-10 诊断代码捕获了几乎所有的缺血性卒中遭遇和转移，而 ICD-9/ICD-10 和 CPT 代码的组合足以识别管理数据集中的溶栓治疗。然而，除了用于识别 EVT 的 ICD 代码之外，MS-DRG 代码也是必要的，这可能是由于对 EVT 相关的 MS-DRG 代码的优惠补偿可以激励准确的编码。数据可能从第三方获得，并且不公开。本研究使用了由加州全州卫生规划和发展办公室维护的非公开数据。所有数据请求应直接向该组织提出。