You can create unlimited rating fields in review submission form, for rating abstract submissions. Each rating shall have a scale from 1 to 10 (so as to calculate the average rating). So, for example, you have three criteria on which you are reviewing an abstract viz. Innovative, Exclusive, Speaking experience.
Now, using the Rating field type in Form builder, you would create these three rating fields in review submission form. These rating fields shall now be displayed in the review submission form for reviewers to submit their review. Rating is a special field type to let reviewers rate abstracts on a scale of 1 to 10 for the given criteria.
Also, use the Separator field in Form builder, to display the Scale legends i.e. 1. Really not good enough. 2. Poster level material etc.