To achieve 100% decision coverage, you must ensure every decision in the code has been evaluated both to true and false. Given the code:
If x > y and z = 3 statement1 elseif z = 4 statement2 endif;
Two tests are required:
* Test 1: Set x > y true and z = 3 to evaluate the first decision as true and execute statement1.
* Test 2: Set z = 4 (ensuring the first condition x > y and z = 3 evaluates to false) to evaluate the elseif condition as true and execute statement2.
This testing ensures that both branches of the decision have been evaluated.