Classification, Structuring, and Assessment of Evidence for Safety -- A Systematic Literature Review

Safety assurance and certification are amongst the most expensive and time-consuming tasks in the development of safety-critical systems. Demonstration of compliance with safety standards involves providing evidence that the standards' safety criteria are met. To handle large collections of evidence effectively, safety professionals need knowledge of how to classify different types of evidence, how to structure the evidence, and how to assess it. This paper takes a step towards developing such a body of knowledge by conducting a Systematic Literature Review (SLR). Specifically, the SLR identifies and classifies the information and artefacts considered as evidence for safety, examines existing techniques for evidence structuring and assessment, and summarizes the challenges noted in the literature in relation to safety evidence. The paper, to our knowledge, is the first systematic review on the topic of safety evidence. The results we present are particularly relevant to practitioners seeking to better understand the evidence requirements for safety certification, as well as to researchers conducting research in this area.