Adding a prefix to the MR number can be done only by a person with admin capability.
1. Click on the Setup from the main menu and choose Practice.
2. The Practice page will be displayed as shown in Image 1.
3. Click on the 
button to open the General tab of Practice Options page.
4. In the Generate MR# Using field, select Sequential#. A prefix can be attached only for sequential generation. Prefix can be a combination of 5 alphanumeric characters (A-Z, 0-9). No special characters are allowed as the prefix.
5. Click on the Save button to save the changes.