## 3 Methodology

Table 2: Inclusion and exclusion criteria. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Keywords Searched** & **Database** & **Delimitation Criteria** & **No. of Papers** \\ \hline “digital payment” AND “digital payment system” OR & Web of Science & **Publication stage:** Final & 37 \\ “digital payment” AND emerging AND technology OR & & **Document types:** & \\ “digital payment”AND risks OR & Scopus & (Journal Articles and proceeding reviewed papers) & 106 \\ “digital payment”AND challenges & & **Language:** (english) & \\ \hline \multicolumn{4}{c}{Total} & 143 \\ \hline \multicolumn{4}{c}{Subtracted “Papers with no full text access”} & \(-21\) \\ \hline \multicolumn{4}{c}{Subtracted “Duplications”} & \(-22\) \\ \hline \multicolumn{4}{c}{**Total articles retrieved through the search process (downloaded for reading)**} & **100** \\ \hline \hline \end{tabular}
\end{table} 
Table 3: The searching and selection process. specific applications, published book chapters, lecture notes and grey literature, such as company reports, working papers and government documents, were excluded. In total, 26 articles were weeded out in this step and only 74 articles were considered for quality screening in the next step (see Table 4). _Step 5: Quality Screen_--The 74 eligible articles selected through the previous step were then screened for quality by closely reading through the content (full text) of each article. Since only empirical studies were included in this study to ensure the quality of the review, the quality screening mainly judged the methodological validity and reliability of the findings. Thus, the articles were screened out based on assessment of methodology employed in the study, including the data collection methods and findings [29]. For example, quantitative studies were assessed based on the reliability of the methodology, such as to check if the study applied acceptable statistical methods. For scoring qualitative studies, the guidelines from [PERSON] [30] were used, which highlight the importance of argumentation analysis. The studies were examined on the basis of how the arguments were built and if the basis of the arguments was derived from inference, assertion or supposition [30]. Thus, the studies providing valid and quality arguments for their claims were included. Additionally, the articles' practical and theoretical contributions were assessed and studies with clear and valid contributions were included. As a result of this step, 22 articles were screened out and only 52 articles were selected for the final review. Further, 6 additional relevant articles were selected through backward citation searching and, in total, 58 empirical articles were finally confirmed and selected for the review (see Table 4). _Step 6: Data Extraction_--With practical and quality screening completed, a final set of 58 articles was selected and confirmed for the review. After completing the reading, we started extracting the data from each article. The data extraction form (excel form), defined and piloted during the protocol (step 2), was used to record the data accurately [31]. The process for extracting and preparing the data included identifying and recording the digital payment technologies investigated in the articles, along with the key findings, to specifically address the first research question.