Where used:
| Data Set | HES - CDS Data items cross referenced by HES Item - Table 2 | references in description PRIMARY OPERATION (OPCS-4) |
| Data Element | PRIMARY PROCEDURE DATE | references in description PRIMARY OPERATION (OPCS-4) |
| Data Element | THIRD OPERATION (OPCS-4) | references in description PRIMARY OPERATION (OPCS-4) |
| Supporting Information | Primary Procedure Date | references in description PRIMARY OPERATION (OPCS-4) |