A protected blister package assembled by a pharmacist for a patient has the correctness of its assembly confirmed by checking the correct correlation of three binary codes respectively appearing on three components of the package. The first component comprises a blister sheet loaded with the prescribed medication doses； the second component comprises a backing sheet sealing the medication doses in the cavities of the package blisters； and the third component comprises a protective card to be folded around the blister package after it has been attached to the card. Prior to assembly of the blister package two of the binary codes are printed on the backing sheet and the third binary code is printed on the card. During assembly of the package a portion of the backing sheet bearing one of its two codes is transferred to a predetermined position on the blister sheet. After assembly of the protected blister package the three binary codes are scanned to confirm that the package has been correctly assembled.
