The folks at Behavior Change for Good at UPenn Wharton have released a guide to understanding and conducting “megastudies”.
Megastudies are large field experiments that test multiple solutions simultaneously to see which one(s) performs best. The goal is to “generate new policy relevant behavioral insights”.
Learn more in their open-access article at PNAS Nexus: https://academic.oup.com/pnasnexus/article/1/5/pgac214/6751928