BACKGROUND The thoracic simulated allocation model (TSAM) is used by the Scientific Registry of Transplant Recipients to predict the relative effect of organ allocation policy changes. A new lung allocation policy changing the first unit of allocation from donation service area to 250 nautical miles took effect on November 24, 2017. We studied TSAM's ability to correctly predict trends caused by changes in allocation policy. METHODS We compared the population characteristics from the TSAM cohort, 6,386 lung transplant candidates from 2009 to 2011, with the observed cohort of 7,601 candidates from the year before the policy change on November 24, 2017, and the year after. Simulations were run 10 times. Waitlist mortality and transplant rates were calculated and compared with observed mortality and transplant rates in the years before and after the policy change. RESULTS TSAM correctly predicted no change in overall waitlist mortality or transplant rates with the policy change. Observed waitlist mortality values were higher, as were transplant rates, because of increased organ donation and population change. TSAM predicted increased transplant rates for diagnosis group D (idiopathic pulmonary fibrosis), decreased rates for group A (chronic obstructive pulmonary disease), and increased rates for candidates with lung allocation score ≥50, but these changes did not occur in the waitlist and transplant populations after the policy change. CONCLUSIONS TSAM correctly predicted the relative trends caused by a change in allocation policy but smaller sub-group predictions were not seen.

中文翻译：

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验证胸腔模拟分配模型预测对更广泛的供体肺地理共享对移植等待清单结果的影响。

背景技术胸腔模拟分配模型（TSAM）被移植受体科学注册机构用来预测器官分配政策变化的相对影响。一项新的肺部分配政策于2017年11月24日生效，将分配的第一单位从捐赠服务区域更改为250海里。我们研究了TSAM正确预测分配政策变更导致的趋势的能力。方法我们比较了TSAM队列的人群特征（2009年至2011年的6,386例肺移植候选者）与观察到的2017年11月24日政策变更前一年及后一年的7,601例肺移植候选者。模拟运行了10次。计算了候补名单的死亡率和移植率，并将其与政策变更前后几年中观察到的死亡率和移植率进行了比较。结果TSAM正确地预测，随着政策的改变，总体候补名单死亡率或移植率不会发生变化。观察到的候补名单死亡率值较高，移植率也较高，这是因为器官捐献和人口变化增加了。TSAM预测诊断D组（特发性肺纤维化）的移植率将增加，A组（慢性阻塞性肺疾病）的移植率将降低，肺分配得分≥50的候选人的移植率将增加，但是这些变化在候补名单和移植中均未发生政策改变后的人口。