Mapping the literature of internal auditing in Europe: a systematic review and agenda for future research

Purpose Although many firms are investing considerable resources in building and designing strong and effective internal auditing (IA) to improve corporate governance and internal control processes, IA literature is still relatively fragmented. Therefore, this paper aims to provide a systematic review of studies on IA in 27 European countries and the UK. Design/methodology/approach Based on the Scopus database, 142 papers published between 1987 and 2022 were analyzed. This study focused on evaluating and analyzing the characteristics of literature and the themes investigated with a focus on four key aspects: governance, the effectiveness of IA, the relationship between internal auditors and other parties and risk management to provide directions for future research. Findings This study found that IA literature did not provide the integrated knowledge of internal audit functions (IAFs) and the factors that could contribute to their implementation as required. The results showed that the UK, Greece and Italy dominate the published literature in terms of the number of studies. There are a few studies that investigate IA in private institutions and nonprofit organizations. Interestingly, a vast majority of studies are not based on theoretical grounds. The results also showed that there is an absence of studies that discuss the impact of cultural and political systems as well as the demographic characteristics of auditors on the implementation of IAFs. Originality/value This study is useful for researchers, organizations and regulators because it contributes to the literature by highlighting the intellectual development of IA in the European countries and the UK, providing several directions for future studies. To the best of the authors' knowledge, this research is the first study to use a systematic review approach in evaluating the intellectual development of IA research in European countries, identifying areas and elements that received less attention in previous studies and providing a roadmap for future studies.