I need to perform a computation of reliability of a 5-point Likert scale having 6 items. From a factor analysis I found that my scale is a multidimensional scale (3 factors), so I cannot use Cronbach's alpha to compute reliability. I have seen in several papers that it is possible to use the multidimensional extension of the McDonald's omega. Does the
omega function in the psych package allow to do this?
Also, is there an R function to compute the Stratified alpha?