SUMMARY Given the current state of the art in research, practitioners are faced with the challenge of choosing scripted testing (ST) or exploratory testing (ET). This study aims at systematically incorporating strengths of ET and ST in a hybrid testing process to overcome the weaknesses of each. We utilized systematic review and practitioner interviews to identify strengths and weaknesses of ET and ST. Strengths of ET were mapped to weaknesses of ST and vice versa. Noblit and Hare's lines‐of‐argument method was used for data analysis. The results of the mapping were used as input to codesign a hybrid process with experienced practitioners. We found a clear need to create a hybrid process as follows: (i) both ST and ET provide strengths and weaknesses, and these depend on some particular conditions, which prevents preference of one approach to another; and (ii) the mapping showed that it is possible to address the weaknesses in one process by the strengths of the other in a hybrid form. With the input from literature and industry experts, a flexible and iterative hybrid process was designed. Practitioners can clearly benefit from using a hybrid process given the mapping of advantages and disadvantages. Copyright © 2013 John Wiley & Sons, Ltd.

Abstract. This study presents an experimental study comparing the testing quality of a Hybrid Testing (HT) process with the commonly used approaches in industry: Scripted Testing (ST) and Exploratory Testing (ET). The study was conducted in an international IT service company in Sweden with the involvement of six experienced testers. Two measures were used for comparison: 1) defect detection effectiveness (DDE) and 2) functionality coverage (FC). The results indicated that HT performed better in terms of DDE than ST and worse than ET. In terms of FC, HT performed better than ET, while no significant differences were observed between the HT and ST. Furthermore, HT performed best for experienced testers, but worse with less experienced testers.