Data from 208 parallel clinical trials with quantitative outcome published in years 2004, 2007, 2010 and 2013. The main collected variables are: title; link to PubMed abstract; type of outcome (measur
To evaluate variance homogeneity among groups for clustered data, Iachine et al. (Robust tests for the equality of variances for clustered data. J Stat Comput Simul 2010;80(4):365–377) introduced an e
1of the F-test (Variances are equal) is rejected for probability values less than 5%. The mean and standard deviation of stiffness of both tasks, their normalized difference , the percentage of data d
