Departamento de Estadística, Facultad de Ciencias, Universidad Nacional de Colombia, Mosquera, Colombia.
Corporaciòn Colombiana de Investigaciòn Agropecuaria - AGROSAVIA, Sede Central, Mosquera,Colombia.
Stat Methods Med Res. 2023 May;32(5):1033-1050. doi: 10.1177/09622802231158736. Epub 2023 Mar 15.
A model for cross-over designs with repeated measures within each period was developed. It was obtained using an extension of generalized estimating equations that includes a parametric component to model treatment effects and a non-parametric component to model time and carry-over effects; the estimation approach for the non-parametric component is based on splines. A simulation study was carried out to explore the model properties. Thus, when there is a carry-over effect or a functional temporal effect, the proposed model presents better results than the standard models. Among the theoretical properties, the solution is found to be analogous to weighted least squares. Therefore, model diagnostics can be made by adapting the results from a multiple regression. The proposed methodology was implemented in the data sets of the cross-over experiments that motivated the approach of this work: systolic blood pressure and insulin in rabbits.
建立了一种用于每个时期内重复测量的交叉设计的模型。它是使用广义估计方程的扩展得到的，该扩展包括一个参数组件来模拟治疗效果，以及一个非参数组件来模拟时间和延续效果；非参数组件的估计方法基于样条。进行了一项模拟研究来探索模型特性。因此，当存在延续效应或功能时间效应时，所提出的模型比标准模型具有更好的结果。在理论性质中，该解决方案类似于加权最小二乘法。因此，可以通过采用多元回归的结果来进行模型诊断。所提出的方法学已应用于促使这项工作的交叉实验数据集：兔子的收缩压和胰岛素。
