I would like to know if it is possible to use items with different scales to compute a single variable. For example for the variable "authonomy" I would like to include 4 items for the variable computation. Three questions are with yes/no answer, e.g., "Are you able to choose your methods of work?", and one question is "Are you able to apply your own ideas in your work?" and has a 5-point-scale (1=always, 5=never). Thanks for your support and sorry for my English! :-) Ade

I would like to know if it is possible to use items with different scales to compute a single variable. For example for the variable "authonomy" I would like to include 4 items for the variable computation. 

Three questions are with yes/no answer, e.g., "Are you able to choose your methods of work?", and one question is "Are you able to apply your own ideas in your work?" and has a 5-point-scale (1=always, 5=never).