The effect of experience on the test-driven development process

We conducted a quasi-experiment to compare the characteristics of experts’ and novices’ test-driven development processes. Our novices were 11 computers science students who participated in an Extreme Programming lab course, the expert group consisted of seven professionals who had industrial experience in test-driven development. The novices as well as two of the experts worked in a laboratory environment whereas the remaining five experts worked in their office. The experts complied more to the rules of test-driven development and had shorter test-cycles than the novices. The tests written by the experts were of higher quality in terms of statement and block coverage as well. All reported results are statistically significant on the 5% level. We conclude that the results of studies which evaluate performance of test-driven development using subjects inexperienced in TDD are not easily generalisable.