Moving, initializing or setting uninitialized data

Use an INITIALIZE or SET statement to initialize a table or data item when you suspect that a problem might be caused by residual data in those fields.

If the problem happens intermittently and not always with the same data, it could be that a switch was not initialized but is generally set to the right value (0 or 1) by chance. By using a SET statement to ensure that the switch is initialized, you can determine that the uninitialized switch is the cause of the problem or remove it as a possible cause.

Related references  
INITIALIZE statement (Enterprise COBOL for z/OS® Language Reference)  
SET statement (Enterprise COBOL for z/OS Language Reference)