When generating an invoice you can specify from the "Invoice" tab of "My Settings" which fields appear on your invoices.

You can decide whether you include:

Client name & address
Date of birth
Hospital #
NHS #

Additionally you can select up to 3 custom fields to include which is explained in the article linked below: 

How do I add custom fields to my invoice?

Updated on: 23 / 12 / 2020