2. Survey methodology

This systematic review presented herein was conducted by the authors of this article following the systematic review
procedures described in Kitchenham (11). Specifically, we sought to tackle the following problems: (a) we sought to
summarise and compare existing KG-based explainable AI approaches, and (b) we sought to determine the contributions
of various approaches in terms of how and where they used KGs for the purposes of explainability. An overview of our
search methodology, including the number of articles retrieved in each step, is shown in Figure 1 and described in detail
below. Furthermore, a forward and backward search (2) was also conducted to complement the list of relevant research
articles.

3. Related surveys
Knowledge-graph-based explainable AI- A systematic review