  Background: Given the social aspects of Software Engineering (SE), in the
last twenty years, researchers from the field started using research methods
common in social sciences such as case study, ethnography, and grounded theory.
More recently, case survey, another imported research method, has seen its
increasing use in SE studies. It is based on existing case studies reported in
the literature and intends to harness the generalizability of survey and the
depth of case study. However, little is known on how case survey has been
applied in SE research, let alone guidelines on how to employ it properly.
Aims: This article aims to provide a better understanding of how case survey
has been applied in Software Engineering research. Method: To address this
knowledge gap, we performed a systematic mapping study and analyzed 12 Software
Engineering studies that used the case survey method. Results: Our findings
show that these studies presented a heterogeneous understanding of the approach
ranging from secondary studies to primary inquiries focused on a large number
of instances of a research phenomenon. They have not applied the case survey
method consistently as defined in the seminal methodological papers.
Conclusions: We conclude that a set of clearly defined guidelines are needed on
how to use case survey in SE research, to ensure the quality of the studies
employing this approach and to provide a set of clearly defined criteria to
evaluate such work.
