## 4 Results
### Heuristic Evaluation Using Automated Tools
#### 4.1.1 Principles  
In this section, we start with the common issues in the three systems. Regarding the four principles, perceivable was the most violated principle by all the systems, followed by operable, then robust. As shown in Figure 5, the errors corresponding to the perceivable principle alone represented about 73% of the total errors. This principle concerns the ability of the user to recognize the displayed information using any of their senses. Most of the perceivable errors were not compliant with two success criteria. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**System** & **Principle** & **AChecker** & **HTML\_CodeSniffer** & **Total Validator** & **Total** \\ \hline \multirow{4}{*}{Noor} & 1. Perceivable & 16 (A) & 14 (A) & 111 (A) & 173 \\  & 31 (AA) & & 1 (AA) & 1 (AA) & 128 \\  & 2. Operable & 34 (A) & 5 (A) & 51 (AA) & 128 \\  & 3. Understandable & 15 (A) & 6 (A) & 29 (A) & 50 \\  & 4. Robust & - & 72 (A) & 36 (A) & 108 \\ \hline \multirow{4}{*}{Faris} & 1. Perceivable & 168 (A) & 151 (A) & 322 (A) & 699 \\  & 2. Operable & - & 5 (A) & 33 (A) & 53 \\  & 3. Understandable & 6 (A) & 4 (A) & 6 (A) & 16 \\  & 4. Robust & 1 (A) & 7 (A) & 12 (A) & 20 \\ \hline \multirow{4}{*}{iEN} & 1. Perceivable & 269 (A) & 47 (A) & 106 (A) & 486 \\  & 2. Operable & - & - & 64 (A) & 64 \\  & 3. Understandable & 12 (A) & 5 (A) & 3 (A) & 20 \\  & 4. Robust & 4 (A) & 34 (A) & 11 (A) & 49 \\ \hline \hline \end{tabular}
\end{table} 
Table 7: Total number of errors based on the principles. Guideline 1.1 (Text Alternatives)  
1.1.1: Non-text Content (Level A)  
Images were used widely as links; however, these images did not have an ALT attribute. The ALT attribute is an alternative text that can be used to describe the purpose of the link. This issue is critical since many screen readers are unable to read ALT; accordingly, VI users will not recognize the existence of a link, thus negatively impacting the time that VI users take for browsing or performing tasks. Moreover, the absence of the ALT attribute in image tags is a big issue, especially when the image contains important information, such as statistical data or important announcements. Guideline 1.3 (Adaptable)  
1.3.1: Info and Relationships (Level A)  
Many pages used regular text as headings and some of them had more than one h1 element. The correct usage of headings will allow screen readers to identify headings and read the text as a heading with its level, thus allowing VI users to get to the content of interest quickly. To overcome this issue, the heading tag must not be used unless the text is intended to be a heading. Moreover, the proper hierarchical h1-h6 should be used to denote the level (importance) of the headings by making the title of the main content h1 and changing other h1 elements to a lower heading level. The remaining errors did not comply with the following success criteria. Guideline 3.1 (Readable)  
3.1.1: Language of the Page (Level A)  
The default language of many pages was identified as the English language, while the main language of these pages was Arabic. Moreover, the lang attribute was missing from some pages. The lang attribute is important for many reasons, including the fact that it allows screen readers to pronounce words in the appropriate accent and offers definitions using a dictionary. Therefore, the lang attribute must be employed in a way that reflects the main language of the web page. Furthermore, the lang attribute should be added to allow screen readers to pronounce words correctly. In the previous subsection, we discussed the common accessibility issues identified in all three systems. In addition, we were able to identify other violations of accessibility principles in some of the systems. Next, we will discuss these errors in detail. Guideline 4.1 (Compatible)  
4.1.1: Parsing (Level A)  
In the iEN system, there were many duplications of the id attribute; therefore, some elements had the same id value.