## 3 Materials and Methods
### Heuristic Evaluation Using Automated Tools  
Heuristic evaluation is a method for assessing computer software usability based on specific principles. It can be done by either usability experts or through automated tools. Many automated tools can assist with identifying accessibility issues. According to [36], the effectiveness of automated tools depends on reaching a high level of three aspects: coverage, completeness, and correctness. However, the performance of a single tool can vary at achieving different levels of these aspects. As an example, SortSite and Total Validator show the highest coverage and completeness, while AChecker has high correctness. Therefore, to increase the tool's effectiveness, the authors of [36] suggested employing different approaches. Accordingly, four evaluation tools, namely, Total Validator, HTML_CodeSniffer, SortSite, and AChecker, were adopted to perform the accessibility evaluation tests. These tools were the most commonly used tools for accessibility assessments in the reviewed studies, including [6; 9; 12; 21]. Total Validator is an accessibility tool that comprises an all-in-one validator. It helps to ensure that the website is accessible based on the WCAG and US Section 508 guidelines, that it uses valid HTML and CSS, has no broken links, and is free from spelling mistakes. Total Validator has three versions: test (lowest version), which performs accessibility and HTML validations and only outputs a summary; the basic version validates spelling and link checking and provides detailed results; the pro version validates an entire website or multiple websites in one go, checks the CSS against World Wide Web Consortium (W3C) standards, and checks the password-protected areas of websites. In our study, we used the basic version because it provided the required features to complete the evaluation process. HTML_CodeSniffer, which is an open-source, online checker tool, is written in the JavaScript language; therefore, it checks the code by using the browser without the need for any server-side handling. Furthermore, it evaluates websites based on different standards, including the WCAG 2.0 and Section 508, and provides step-by-step correction methods. The third tool was SortSite, which is a one-click web site testing tool used by federal agencies, Fortune 100 corporations, and independent consultancies. The tool is available as a desktop application for Mac or Windows and is also available as a web application. It was released in 2007 and has been widely used by many entities since then. The web version assesses 10 pages of the entered URL at a time, whereas the desktop version checks only the uploaded page. Finally, AChecker, which is an open-source automatic tool, assesses compliance with different accessibility guidelines, including Barrierefie Informationstechnik-Verordnung (Barrier-Free Information Technology Regulation; Germany) (BITV) 1.0 (level 2), Section 508, Stanca Act, WCAG 1.0, and WCAG 2.0. Moreover, it provides three methods for checking the accessibility of a specific website: pasting a URL, uploading an HTML page, and pasting the source code of the HTML page. \begin{table}
\begin{tabular}{l l l} \hline \hline  & **System** & \multicolumn{2}{c}{**Selected Functionalities**} \\ \hline \multirow{2}{*}{**1**} & \multirow{2}{*}{Noor System} & \(\bullet\) Logging in \\  & & \(\bullet\) Entering skills/grades \\  & & \(\bullet\) Borrowing a book \\ \hline \multirow{2}{*}{**2**} & \multirow{2}{*}{Faris System} & \(\bullet\) Logging in \\  & & \(\bullet\) Requesting a vacation \\  & & \(\bullet\) Requesting a salary identification certificate \\ \hline \multirow{3}{*}{**3**} & \multirow{3}{*}{iEN System} & \(\bullet\) Logging in \\  & & \(\bullet\) Playing interactive content \\ \cline{1-1}  & & \(\bullet\) Searching for course plans \\ \cline{1-1}  & & \(\bullet\) Downloading course content \\ \hline \hline \end{tabular}
\end{table} 
Table 1: The final selected functionalities for each system.