How to implement Likert Scale with EntityForm?
[...] you can make form elements that don't have directly corresponding elements in the FAPI. The "grid" component is a good example of this, and in this case, I think it's exactly what you're wanting. You can effectively create a likert scale by creating "options" along the top with these keys:


-2|Strongly disagree
-1|Disagree
0|Neutral
1|Agree
2|Strongly agree


Source: https://www.drupal.org/node/291658