The Wellcome-Wolfson Institute for Experimental Medicine, Queen's University Belfast, UK.
The Wellcome-Wolfson Institute for Experimental Medicine, Queen's University Belfast, UK.
Respir Med. 2018 Dec;145:206-211. doi: 10.1016/j.rmed.2018.10.030. Epub 2018 Nov 1.
Multiple Breath Washout (MBW) to measure Lung Clearance Index (LCI) is increasingly being used as a secondary endpoint in multicentre bronchiectasis studies. LCI data quality control or "over-reading" is resource intensive and the impact is unclear.
To assess the proportion of MBW tests deemed unacceptable with over-reading, and to assess the change in LCI (number of turnovers), LCI coefficient of variation (CV%) and tidal volume (VT) CV% results after over-reading.
Data were analysed from 250 MBW tests (from 98 adult bronchiectasis patients) collected as part of the Bronch-UK Clinimetrics study in 5 UK centres. Each MBW test was over-read centrally using pre-defined criteria. MBW tests with <2 technically valid and repeatable trials were deemed unacceptable to include in analysis. In accepted tests, values for LCI, LCI CV% and VT CV% before and after over-reading, were compared.
Insufficient data was collected in 10/250 tests. With over-reading, 30/240 (12%) were deemed unacceptable to include in analysis. In those accepted tests, overall the change in LCI, LCI CV% and VT CV% with over-reading was not statistically significant. When MBW new sites were compared to MBW expert sites, the change in LCI with over-reading was significantly greater in MBW new sites (p = 0.047). Data suggests that over-reading could be important up to at least 12 months post initiation of MBW activity.
MBW over-reading was important in this study as 12% of tests were considered unacceptable. Over-reading improved test result accuracy in sites new to MBW.
多次呼吸冲洗（MBW）测量肺清除指数（LCI）越来越多地被用作多中心支气管扩张症研究的次要终点。LCI 数据质量控制或“重读”需要大量资源，其影响尚不清楚。
评估重读后认为不可接受的 MBW 测试比例，并评估重读后 LCI（换气次数）、LCI 变异系数（CV%）和潮气量（VT）CV%结果的变化。
分析了来自 5 个英国中心的 Bronch-UK Clinimetrics 研究中收集的 250 次 MBW 测试（来自 98 名成人支气管扩张症患者）的数据。每个 MBW 测试都由中央使用预定义标准进行重读。如果<2 次技术上有效且可重复的试验，则认为 MBW 测试不可接受，不包括在分析中。在可接受的测试中，比较重读前后 LCI、LCI CV% 和 VT CV%的值。
在 10/250 次测试中收集的数据不足。重读后，30/240（12%）被认为不可接受，不包括在分析中。在那些可接受的测试中，重读后 LCI、LCI CV% 和 VT CV% 的总体变化没有统计学意义。当比较 MBW 新站点和 MBW 专家站点时，重读后 LCI 的变化在 MBW 新站点中明显更大（p=0.047）。数据表明，重读在至少 12 个月后 MBW 活动开始时可能很重要。
在这项研究中，MBW 重读很重要，因为 12%的测试被认为不可接受。重读提高了 MBW 新站点测试结果的准确性。
