Dear Eric, I read a couple of interesting articles on this recently. 

Vaccination incentives in various US states, from the New York Times:

https://www.nytimes.com/2021/05/03/us/Coronavirus-vaccine-appointment-incentives.html

The New Jersey “Shot and a Beer” program being a notable example:

https://covid19.nj.gov/faqs/nj-information/slowing-the-spread/what-is-the-new-jersey-%E2%80%9Cshot-and-a-beer%E2%80%9D-program-what-breweries-are-participating  

Incentives by country, from the Guardian:

https://www.theguardian.com/australia-news/2021/may/09/from-grannies-flipping-the-bird-to-free-beer-the-creative-approaches-to-promoting-covid-vaccines

It will be interesting to read the studies on which incentives prove the most effective. Most likely it will be highly context-specific.

Hope this is of use!

Thank Dan for the information

I am continuing collecting articles, also trying to sort out information through some indicators (Country, Incentive type, Company, Where, Limitation, Probe, How it works, etc.)

Let's see what we can find out of it

Any further information, please do not hesitate to reach me

Warm regards,

Eric