## 4 Results
### Effectiveness  
The effectiveness results are presented in Table 10. We noticed that none of the tasks were performed successfully without any help, except for only one participant in the iEN system. The participant was able to complete the log-in task without any help. Moreover, most of the participants either completed the task with help or did not complete it. This was due to many elements in the user interface being unreadable by the screen readers and/or unreachable by the tab key. Furthermore, the log-in task was the only one that was completed (with help) by all participants in all three systems; this might be due to being a common task in all the systems. However, we found that the step of entering the CAPTCHA image code was not performed by any of the participants due to the screen reader's inability to read it. Because of that, the moderator had to read the code loudly for the participants. Moreover, the participants faced difficulties while typing the password as they were not familiar with the English keyboard, so they had difficulties in locating the characters. Furthermore, the VI participants were unable to switch the language to English to enter the username and password. In the next paragraphs, we discuss the results of the remaining tasks that were related to each system separately. First, we show the results of the Noor system tasks. It should be noted before presenting the results that one of the participants was partially blind, so she preferred to use the mouse as the main input device during the session. The other two participants were totally blind and therefore they used only the keyboard when performing the tasks. In task 2 (enter skills/grades) and task 3 (borrow a book), the two keyboard-using participants failed to complete the task's last step, which was the step of clicking the search button (see Figures 8 and 9). This was due to the search button being unreachable by the tab key. However, the third participant, who was a mouse user and partially blind, was able to successfully complete the task. Still, it was completed after the help of the moderator, who read the unreadable dropdown menu elements and labels. Regarding the results of the Faris system tasks, we found the following. As for the \"request a vacation\" and \"request a salary identification\" tasks, we observed a variation in the users' performances, which may be due to the differences in their experience. However, we noticed that all participants (novice and expert) faced difficulties and needed instructions when they reached the \"fill in the request form\" step. According to our observations, this step had many fields that needed to be filled in, especially the start and end date of the vacation, which used a calendar and the reader was not able to read it. Moreover, it is good to mention that one of the participants failed to complete the tasks, and according to the pre-questionnaire, she had not used the Faris system before. Furthermore, in the \"request a vacation\" task, we found that some participants did not know the correct type of leave (some of them chose \"emergency leave\" when the scenario was about \"sick leave\"). As for the results of the iEN system with the \"download course content,\" \"play interactive content,\" and \"search for a course plan\" tasks, we found the following. Only two of the participants completed the tasks. One of them was the visually impaired user and she completed the tasks with hints, while the second was one of the three blind participants and completed the tasks with help from the moderator. Moreover, two of the blind participants refused to complete the tasks. Efficiency  
The efficiency was measured using the completion time, as shown in Table 11.  
Regarding the Noor system, it had the lowest completion time compared to the other systems. Moreover, we found that the \"enter skills/grades\" task had the highest completion time. As for the Faris system, we observed that the \"request a vacation\" task was the most time-consuming task with an average of 22 min.