Query-Index
This property is used in conjunction with the Item-Value and Hidden-Data properties to retrieve the value of a specific item and to manage the hidden data bind to the item.
Each item is identified by a number that corresponds to its position in the list, starting at 1.
 
Example - Get the value of a combo-box item
procedure division.
...
  modify  screen-1-co-1 query-index 3
  inquire screen-1-co-1 item-value my-item-var
...