Quantifying the cost in power of ignoring continuous covariate imbalances in clinical trial randomization.
Quantifying the cost in power of ignoring continuous covariate imbalances in clinical trial randomization.
复制标题
DOI：
10.1016/j.cct.2010.11.005
复制
发表时间：
2011-03
影响因子：
2.2
通讯作者：
Palesch Y
中科院分区：
文献类型：
--
作者：
Ciolino J;Zhao W;Martin R;Palesch Y
由于临床试验中连续基线协变量的潜在严重失衡，我们研究了在逻辑回归模型的治疗分配设计中忽略这些协变量平衡的统计能力成本。基于急性缺血性脑卒中治疗临床试验的数据，计算机模拟用于创建从最佳基线协变量平衡到最坏可能失衡的不同场景，在两个极端之间存在多个平衡水平。评估在简单随机化下每种情况发生的可能性。检验了主效试验对治疗的功效。我们的模拟结果表明，最坏的可能不平衡是极不可能的，但它仍然可以在简单的随机分配下发生。此外，如果忽略重要的连续协变量的平衡分布，即使在重要协变量的分析中进行调整，功率损失也可能是不平凡的。这种情况虽然不太可能发生，但对于样本量小的试验和对主要结果影响较大的协变量来说，情况更为严重。这些结果表明，在临床试验的设计阶段，即使在分析时计划对这些协变量进行调整，也应该尝试平衡已知的预后连续协变量。
Motivated by potentially serious imbalances of continuous baseline covariates in clinical trials, we investigated the cost in statistical power of ignoring the balance of these covariates in treatment allocation design for a logistic regression model. Based on data from a clinical trial of acute ischemic stroke treatment, computer simulations were used to create scenarios varying from best possible baseline covariate balance to worst possible imbalance, with multiple balance levels between the two extremes. The likelihood of each scenario occurring under simple randomization was evaluated. Power of the main effect test for treatment was examined. Our simulation results show that the worst possible imbalance is highly unlikely, but it can still occur under simple random allocation. Also, power loss could be nontrivial if balancing distributions of important continuous covariates were ignored even if adjustment is made in analysis for important covariates. This situation, although unlikely, is more serious for trials with a small sample size and for covariates with large influence on primary outcome. These results suggest that attempts should be made to balance known prognostic continuous covariates at the design phase of a clinical trial even when adjustment is planned for these covariates at the analysis.
登录
查看更多内容
影响因子：
8.3
作者：
Ingall, TJ;O'Fallon, WM;Christianson, TJH
通讯作者：
Christianson, TJH
影响因子：
2.7
作者：
ATKINSON, AC
通讯作者：
ATKINSON, AC
DOI：
10.1111/1467-985x.00564
发表时间：
2002-01-01
影响因子：
2
作者：
Atkinson, AC
通讯作者：
Atkinson, AC
影响因子：
18.2
作者：
Kjekshus, J;Dunselman, P;Wikstrand, J
通讯作者：
Wikstrand, J
DOI：
10.1080/03610928008827941
发表时间：
1980-01-01
期刊：
COMMUNICATIONS IN STATISTICS PART A-THEORY AND METHODS
影响因子：
--
作者：
HOSMER, DW;LEMESHOW, S
通讯作者：
LEMESHOW, S