How you capture this will depend on your use cases and how you want to use the data down stream.
If an attribute is always captured in the same way, like "<" then I would use a numeric EA to represent the attribute. I would label the EA name or custom section header with <. With this approach you can still have the EA participate in formulation calculations.
If the attribute is always captured differently "<" ">" etc then I would use multiple fields. Qualitative EA dropdown in one column with the "<" ">" "<=" options and then a numeric EA in another column for the value. The system will not be able to predictively roll this value up so if you do need to perform roll up calculations you will need to write your own dynamic function that knows what to do when a single attribute is defined as < and > etc.
And then of course you could always use a free text field and the user could enter a string "< 5"
Hope this helps,