The 3rd Commandment of Payment by Results: Thy metrics shall be simple

Complexity is almost always the enemy of effective PbR because it inevitably results in unintended consequences. Concern about possible unintended consequences results in worries about gaming the system which, equally inevitably, results in additional measures being taken to address these concerns which involves further complexity which…, well, you get the picture. In this post, I want to make the case for simple, robust measures to assess how effective PbR schemes are in meeting their outcomes.