BR-54
Each Item attribute (BG-32) shall contain an Item attribute name (BT-160) and an Item attribute value (BT-161).
What the rule checks
As the rule set's publisher wrote it. The rule runs on every element the context matches, and fails where the test is false; the validator reports the line of that element.
//cac:AdditionalItemProperty
exists(cbc:Name) and exists(cbc:Value)
Checked with EN 16931 Invoice (UBL), EN 16931 Credit Note (UBL), Croatia eRačun Invoice (UBL), Croatia eRačun Credit Note (UBL)
//ram:ApplicableProductCharacteristic
(ram:Description) and (ram:Value)
Checked with EN 16931 Invoice (CII)