Department of Health Services Research and Policy, London School of Hygiene and Tropical Medicine, London, UK.
Clinical Effectiveness Unit, Royal College of Surgeons of England, London, UK.
Int J Epidemiol. 2023 Feb 8;52(1):214-226. doi: 10.1093/ije/dyac130.
Methods for linking records between two datasets are well established. However, guidance is needed for linking more than two datasets. Using all 'pairwise linkages'-linking each dataset to every other dataset-is the most inclusive, but resource-intensive, approach. The 'spine' approach links each dataset to a designated 'spine dataset', reducing the number of linkages, but potentially reducing linkage quality.
We compared the pairwise and spine linkage approaches using real-world data on patients undergoing emergency bowel cancer surgery between 31 October 2013 and 30 April 2018. We linked an administrative hospital dataset (Hospital Episode Statistics; HES) capturing patients admitted to hospitals in England, and two clinical datasets comprising patients diagnosed with bowel cancer and patients undergoing emergency bowel surgery.
The spine linkage approach, with HES as the spine dataset, created an analysis cohort of 15 826 patients, equating to 98.3% of the 16 100 patients identified using the pairwise linkage approach. There were no systematic differences in patient characteristics between these analysis cohorts. Associations of patient and tumour characteristics with mortality, complications and length of stay were not sensitive to the linkage approach. When eligibility criteria were applied before linkage, spine linkage included 14 509 patients (90.0% compared with pairwise linkage).
Spine linkage can be used as an efficient alternative to pairwise linkage if case ascertainment in the spine dataset and data quality of linkage variables are high. These aspects should be systematically evaluated in the nominated spine dataset before spine linkage is used to create the analysis cohort.
连接两个数据集记录的方法已经很成熟。然而，还需要指导如何连接两个以上的数据集。使用所有“两两链接”-将每个数据集链接到每个其他数据集-是最全面的，但资源密集型的方法。“脊柱”方法将每个数据集链接到指定的“脊柱数据集”，减少了链接的数量，但可能会降低链接的质量。
我们使用 2013 年 10 月 31 日至 2018 年 4 月 30 日期间接受紧急结肠癌手术的患者的真实世界数据比较了两两链接和脊柱链接方法。我们链接了一个包含在英格兰医院住院的患者的行政医院数据集（医院发病统计；HES），以及两个包含结肠癌患者和接受紧急肠道手术的患者的临床数据集。
以 HES 为脊柱数据集的脊柱链接方法创建了一个 15826 名患者的分析队列，相当于使用两两链接方法确定的 16100 名患者的 98.3%。这两个分析队列之间的患者特征没有系统差异。患者和肿瘤特征与死亡率、并发症和住院时间的关联不受链接方法的影响。在链接之前应用资格标准时，脊柱链接包括 14509 名患者（与两两链接相比为 90.0%）。
如果脊柱数据集中的病例确定和链接变量的数据质量较高，脊柱链接可以作为两两链接的有效替代方法。在使用脊柱链接创建分析队列之前，应系统地评估指定脊柱数据集中的这些方面。
