Adding Case Statement to Existing Data Model

Summary

Need assistance with case statement

Content

I am in need of assistance with the following: (1) case statement syntax and (2) adding a case statement to an existing data model

My goal is to create a new field in an existing data model named ‘Score’. The values in this field (Green, Yellow and Red) depends on the total score (see case statement below).  The Total Score field is already in the existing data model. I then want to use this new field ‘Score’ as a parameter.

Here is the case statement - there is something wrong with the syntax:

SELECT TOTAL_SCORE