[fzeindl]

> On the other hand, there is no way to measure the "effectiveness" of TDD as compared to not using it.

There are definitely ways to measure, for example by it's impact on bug resolution time. The following study looks at static code quality, but it could be applied to TDD:

This study is about static code quality, but could be applied to TDD as well. https://www.researchgate.net/publication/359129462_Code_Red_...

[gog]

Bug resolution time is not the only metric of value in software development.

[fzeindl]

I quote myself:

> _for example_ by it's impact on bug resolution time