It is very important before kicking off a program like this to make sure that you evaluate staff access to certain features in your practice management system. I would also implement an approval system for those staff that have the ability to manipulate dollars in the system.
When you base incentives on a moving target it is easy for people to figure out how to manipulate it therefore creating artificial numbers at month end. For example, if Jane is responsible for AR and she has the ability to do write offs/adjustments, with no safety measures in place the month of August for example could be an amazing reduction in your 120+ bucket for AR, especially if Jane is going to be finacially bonused/incentivised based on that end of month number.
Make sure all batches or journals are balanced daily for money collected, adjustments/write offs, and all othe financial activity that occurs in your system. Make sure staff do not share batches or journals for posting purposes.
I don't usually guide to use money/financial bonuses as an incentive. There are lots of other way to incentivise employees that holds a much lower risk such as end of month lunch, a monthly team building exercise, gift card to starbucks etc. Base the incentive on a combination of things such as punctuality, catching someone in the act of doing good box, going above and beyond, clean claims and lowering your denial percent per month (every person in the office impacts clean claims), collections percent.
Don't tell them the specifics of the measures such as raw numbers rather a practice wide initiative to improve overall function of your practice.
Get one of your docs on board to sort of cheer lead and make staff feel appreciated. The feeling of appreciation will naturally foster people to want to do more because they feel good about coming to work.
Enjoy