title: How can I use rowSums() after multiple imputation with MICE package in R
body: <p>I have a short question: <br/><br/>
  I imputed item data using multiple imputation with the MICE package.<br/>
  After imputation, I would like to sum items to a total score.<br/>
  However, my data is now in a mids object, and I can't figure out how to do this simple task.<br/>
  Does anyone have experience with this "problem"?</p>
  
  <p>Best, Leonhard</p>