## 5 Results and Discussion
### Usability Evaluation
#### 5.3.2 System Usability Scale Evaluation  
The System Usability Scale (SUS) was first published in 1986 and included 10 statements, comprising five positive and five negative descriptions. This scale employs a 5-point rating system ranging from \"strongly disagree\" to \"strongly agree\". The user's final responses will be converted into a percentage score. The calculation formula is [\(\mathbb{E}\)(positive description score \(-1\)) + \(\Sigma\)(5 \(-\) negative description score)] \(\times\) 2.5 (where 1 represents strong disagreement and 5 represents strong agreement). With an increment of 2.5 points, SUS scores range from 0 to 100. Research indicates that SUS applies to device systems and products that interact with users, providing an SUS score that is not significantly different from more extensive sample measurements even with a few samples.  
[PERSON] [41] and his colleagues, based on their analysis of 206 SUS usability questionnaires, have scientifically interpreted the final score categories of the questionnaire. An SUS score of less than 50 indicates that users find the usability of the tested system or product unacceptable. If the SUS score is between 50 and 70, it implies that the usability of the  
\begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline
**Methods** & **Design Task** & **Architecture** & \
\begin{tabular}{c} **Structural** \\ **Engineering** \\ \end{tabular} & **Plumbing** &
\begin{tabular}{c} **Electrical** \\ **Engineering** \\ \end{tabular} & **HVAC** \\ \hline
2D drawing & \begin{tabular}{c} Collision Detection \\ Drawing Review \\ \end{tabular} & 34 & 18 & 22 & 39 & 20 & 133 \\ \hline BIM & \
\begin{tabular}{c} Collision Detection \\ Drawing Review \\ \end{tabular} & 7 & 16 & 11 & 20 & 13 & 67 \\ \hline BIM and VR &
\begin{tabular}{c} Collision Detection \\ Drawing Review \\ \end{tabular} & 26 & 15 & 14 & 23 & 14 & 92 \\ \hline \hline \end{tabular}
\end{table}
Table 3: Collision detection and drawing review results of various design specialties under different design methods (unit: article).  
system or product is within an acceptable threshold for users. Conversely, an SUS score above 70 suggests that users are satisfied with the usability of the tested system or product.  
By executing the SUS analysis procedure, this study achieved an average score of 78, which is higher than the 70 suggested by [PERSON] (2018). Therefore, the usability level of this framework falls within the range acceptable to users, indicating a generally favorable reception. Table 4 presents the results of this usability test, retaining the original average scores for the negative items. It shows that the scores received for the five positive descriptions ranged from 3.82 to 4.43. The questions with the highest score address that various functions in this system were well integrated (U5, M = 4.43, SD = 0.87), and users felt very confident using the system (U9, M = 4.15, SD = 0.79). Subsequently, most people learned to use the system very quickly (U7, M = 4.07, SD = 0.85) and would like to use this system frequently (U1, M = 3.94, SD = 0.77). The positive assertion with the lowest score questioned whether the system was easy to use (U3, M = 3.82, SD = 0.95).  
The negative assertions are in the bottom half of Table 4. That is, lower scores correspond to better evaluation. In the sequence, less disagreement (more negative evaluation) occurred regarding the need for the user to learn many things before getting going with the system (U10, M = 2.13, SD = 0.74). Participants partially disagreed that they would need a technical person's support to use this system (U4, M = 2.04, SD = 0.68), and the system needed more consistency (U6, M = 1.88, SD = 0.76). Finally, the items with the most disagreement (more positive evaluation) refer to the system as very cumbersome to use (U8, M = 1.67, SD = 0.91), and the system could have been more complex (U2, M = 1.40, SD = 0.83).