It isn't terribly clear from the abstract and I'm not going to pay for the paper, but it sounds like this is really a comparison of tests vs no tests. That has

It isn't terribly clear from the abstract and I'm not going to pay for the paper, but it sounds like this is really a comparison of tests vs no tests. That has nothing to say about the practice of TDD. This is why this newer study is interesting; it compares to TLD, which allows you to say something about TDD rather than just about testing.