## 2 Method
### Selecting Relevant Papers  
The selection process involved a two-stage screening process. Initially, the papers were evaluated and assessed for relevance and eligibility based on their title and abstract to determine their relevance to the RQ and eligibility criteria. Papers that were assessed as inconsistent with the established inclusion criteria were eliminated from the review process. Subsequently, a full-text assessment was conducted on the remaining papers to determine their suitability for inclusion in the review. The full-text assessment is a crucial step in the systematic review process, ensuring that each article selected for final inclusion aligns well with the study's objectives. During this full-text assessment, we dug deeper into each paper, beyond just the abstract, to gain a comprehensive understanding of its content. Here are some specific points or criteria that were typically considered during this assessment:  
Relevance to the Research Objective: The primary aim was to confirm if the paper directly addressed the research objective; in this case, assessing the resistance of recognition-based graphical password methods to shoulder-surfing attacks.  
\begin{table}
\begin{tabular}{l l} \hline \hline
**Research Questions (RQ)** & **Research Objectives (RO)** \\ \hline RQ1: What are the existing recognition-based methods? & RO1: To identify the existing recognition-based methods. \\ RQ2: What pass-objects are used for authentication in & RO2: To determine the pass-objects used for authentication in these methods. \\ RQ3: What are the strengths and weaknesses of the selected & RO3: To examine the strengths and weaknesses of the selected recognition-based methods. \\ RQ4: How effective are the selected recognition-based methods in terms of usability and security? & RO4: To evaluate the effectiveness of the selected recognition-based methods in terms of security and usability. \\ \hline \hline \end{tabular}
\end{table}
Table 1: Research questions and objectives.  
\begin{table}
\begin{tabular}{l l} \hline \hline
**Inclusion Criteria** & **Exclusion Criteria** \\ \hline Research studies that were published between 2016 and 2023 & Papers that do not focus on RBGP methods \\ Papers that propose or deal with only RBGP schemes & Non-peer-reviewed papers \\ Papers published in the English language & Papers published in languages other than English \\ Peer-reviewed articles and conference papers & \\ \hline \hline \end{tabular}
\end{table}
Table 2: Inclusion and exclusion criteria.  
Study Design and Methodology: We looked at the design of the study, whether it was experimental, observational, or another type, to ensure the methods used were rigorous and could yield reliable results.  
Outcomes and Measurements: The outcomes that the study measured and how these were measured (i.e., the metrics and tools used) were evaluated to ensure they were relevant and would contribute meaningfully to the review.  
Consistency with Other Studies: While not a strict criterion, understanding how the findings of a paper align with or differ from other studies in the field can offer insights into the broader context and the robustness of the findings.  
Contribution to the Field: The potential contribution of the study to the existing body of knowledge was assessed. This could be in terms of novel methodologies, unique findings, or a new perspective on an existing challenge.  
Potential Biases: Any apparent biases, either in terms of the study's funding sources, the authors' affiliations, or the methodology used, were taken into account to ensure the review's integrity.  
Clear Conclusions: The study needed to have clear, well-defined conclusions that could be extracted and synthesized into the systematic review.  
Any disagreements during the selection process were resolved through discussion and consensus among the reviewers.