Baseline correction in a two-way randomized blocks design.
Baseline correction in a two-way randomized blocks design.
复制标题
双向随机区组设计中的基线校正。
DOI：
10.1080/10543409208835040
复制
发表时间：
1992
影响因子：
1.1
通讯作者：
Magee,KN
中科院分区：
文献类型：
--
作者：
Overall,JE;Magee,KN
随机区组设计用于临床精神药理学研究，以检验不同药物治疗的相对有效性取决于接受治疗的患者类型的假设。蒙特卡罗方法用于评估在这种设计中对基线差异进行统计控制的不同方法的充分性，特别关注治疗×块相互作用效应。考虑到通常的假设，协方差分析（ANCOVA）被证明可以提供足够的基线校正，并随后对治疗×块相互作用进行无偏测试，以及随机治疗的主要效果。依赖于简单的前后差异分数和百分比变化分数的测试证明了治疗×块相互作用效应测试中存在严重保守或非保守偏差，这种偏差取决于仅在基线测量中观察到的相应相互作用效应的方向。这是一个严肃的问题，因为随机区组设计中的相互作用效应是针对特定类型患者的药物治疗的特定适应症的主张的共同基础。
Randomized blocks designs are used in clinical psychopharmacology research to test the hypothesis that relative effectiveness of different drug treatments depends on the type of patient being treated. Monte Carlo methods were used to evaluate the adequacies of different approaches to statistical control over baseline differences in such a design with special concern for the treatments × blocks interaction effect. Given the usual assumptions, analysis of covariance (ANCOVA) was shown to provide adequate baseline correction with consequent unbiased tests for the treatments × blocks interaction, as well as the main effect for the randomized treatments. Tests relying on simple pre-post difference scores and percentage change scores evidenced seriously conservative or nonconservative bias in the test for treatments × blocks interaction effect, a bias that depended on the direction of the corresponding interaction effect observed in the baseline measurements alone. This is discussed as a serious matter because the interaction effect in a randomized blocks design is a common basis for the claim of specific indications of drug treatments for particular types of patients.