(Batch) Subtract value directly in if statement?

can I directly subtract a number from a variable in an if statement (example 1), or do I have to subtract the value before and then check for the new value (example 2)? And which would be the correct syntax, if method 1 would work?

example 1: if "%variable%-1"==%other_var% ()

example 2: set variable_minus_1="%variable%-1"; if %variable_minus_1%==%other_var%