The unique device identifier (UDI) is a code consisting of numbers or a combination of numbers and letters that is specific to one medical device. It typically consists of a device identifier (DI) and a production identifier (PI).
The mandatory, fixed portion of the UDI that correlates to the labeler and particular version or model of the device is the DI.
The PI is a conditional and variable part of the UDI that can identify one or more of the following:
- serial number of a specific device
- batch or lot number
- date of device manufacturing
- expiration date of the medical device
- distinct identification code
The UDI is provided in two forms on labels and packages: a form read by a machine using automatic identification and data capture (AIDC) technology and an easy-to-read plain text format.