co-variables
complete-case approach

Предложение целиком:

In total, 40 patients (6%) with missing data on one or more co-variables had these values imputed by an expectation–maximization method [Missing Value Analysis command, SPSS 14.0 (SPSS, Chicago, IL)]. For this, we used all co-variables including information on outcome and lymph node status. All analyses that we report are on the basis of this dataset with imputed values, but we also analyzed the data using a complete-case approach to evaluate the robustness of our findings.

Спасибо заранее!

надежность метода проверена на завершенных случаях с полными данными