National registries play a crucial role in understanding the natural history of cystic fibrosis (CF) and the impact of care delivery and interventions on outcomes. Data on more than 90 000 individuals are captured in CF registries around the world.1 Detailed examination of clinical characteristics, interventions and outcomes, benchmarking CF centres within jurisdictions and international comparisons across healthcare systems can stimulate quality improvement initiatives and drive effective changes in practice. In a 2015 cross-sectional comparison of the US and the UK national CF registries, children in the US had better lung function than their UK counterparts2; these differences persisted into early adulthood. However, both cohort effects and survivor bias could have affected the data interpretation as outlined in an accompanying editorial.3 In this issue of the Journal , addressing some of these confounders, Schlüter and colleagues4 once again compared US and UK registry data, but this time focused on longitudinal trajectories of parallel cohorts limiting the study population to children between 6 and 18 years and those homozygous for the F508del mutation. The mean difference in per cent-predicted FEV1 (ppFEV1) between the US and UK populations at ages 6, 12 and 17 years was approximately 4%, 5% and 6%, respectively. The data suggested that children in the US may also have a slower rate of lung function decline, but the evidence for this was less convincing and dependent on …

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苹果对苹果？国家CF登记处的比较分析

国家登记在了解囊性纤维化 (CF) 的自然史以及护理提供和干预措施对结果的影响方面发挥着至关重要的作用。世界各地的 CF 登记处收集了 90,000 多人的数据。1 对临床特征、干预措施和结果的详细检查、辖区内的 CF 中心基准以及医疗保健系统的国际比较可以激发质量改进举措并推动实践中的有效变革。在 2015 年美国和英国国家 CF 登记处的横断面比较中，美国儿童的肺功能优于英国儿童2；这些差异一直持续到成年早期。然而，队列效应和幸存者偏差都可能影响随附社论中概述的数据解释。3 在本期杂志中，针对其中一些混杂因素，Schlüter 及其同事 4 再次比较了美国和英国的登记数据，但这次侧重于平行队列的纵向轨迹，将研究人群限制在 6 至 18 岁的儿童和纯合子对于 F508del 突变。美国和英国人口在 6、12 和 17 岁时的百分比预测 FEV1 (ppFEV1) 的平均差异分别约为 4%、5% 和 6%。数据表明，美国儿童的肺功能下降速度也可能较慢，但这方面的证据不太令人信服，并且依赖于…… 但这次关注的是平行队列的纵向轨迹，将研究人群限制在 6 至 18 岁之间的儿童和 F508del 突变纯合子的儿童。美国和英国人口在 6、12 和 17 岁时的百分比预测 FEV1 (ppFEV1) 的平均差异分别约为 4%、5% 和 6%。数据表明，美国儿童的肺功能下降速度也可能较慢，但这方面的证据不太令人信服，并且依赖于…… 但这次关注的是平行队列的纵向轨迹，将研究人群限制在 6 至 18 岁之间的儿童和 F508del 突变纯合子的儿童。美国和英国人口在 6、12 和 17 岁时的百分比预测 FEV1 (ppFEV1) 的平均差异分别约为 4%、5% 和 6%。数据表明，美国儿童的肺功能下降速度也可能较慢，但这方面的证据不太令人信服，并且依赖于……