## 4 Results and Discussion
### Experiment  
As discussed above, the Kruskal-Wallis H test was carried out to determine how traditional paper-based, monitor-based, and Oculus Quest 2-based design review tasks would impact the user's CL. The results are shown in Figure 7. An insignificant difference was found in the mental demand of the paper- and monitor-based environments, as well as in the monitor and Oculus Quest 2-based environments. However, there was a statistically significant difference between paper and Oculus Quest 2 environments. No significant difference was in the first two media in temporal demand, and all other medium combinations had significant differences. CL's performance, effort, and frustration elements had no significant difference in all three media. The overall CL results show a statistically insignificant difference (\(p<0.05\)) in all three environments for design review tasks. On the other hand, the immersive environment of Oculus Quest 2 was the most cognitively demanding of these three modalities. [PERSON] and [PERSON] explained that the review task will be impaired or fail if the required CL exceeds the limits of working memory. After the detailed comparison of three design review groups' data based on NASA-TLX, the results show that NIVE participants perceived a lower CL than those who used the IVE methods. \begin{table}
\begin{tabular}{c c c c c c c} \hline \multirow{2}{*}{**CL Dimension**} & \multirow{2}{*}{**Medium**} & \multicolumn{3}{c}{**Kolmogorov–Smirnov***} & \multicolumn{3}{c}{**Shapiro–Wilk**} \\ \cline{3-8}  & & **Statistic** & **df** & **Sig.** & **Statistic** & **df** & **Sig.** \\ \hline \multirow{3}{*}{Mental Demand} & Paper & 0.229 & 32 & 0.000 & 0.864 & 32 & 0.001 \\  & Monitor & 0.220 & 32 & 0.000 & 0.883 & 32 & 0.002 \\  & Oculus Quest 2 & 0.205 & 32 & 0.001 & 0.912 & 32 & 0.013 \\ \hline \multirow{3}{*}{Temporal Demand} & Paper & 0.273 & 32 & 0.000 & 0.803 & 32 & 0.000 \\  & Monitor & 0.275 & 32 & 0.000 & 0.783 & 32 & 0.000 \\  & Oculus Quest 2 & 0.224 & 32 & 0.000 & 0.900 & 32 & 0.006 \\ \hline \multirow{3}{*}{Performance} & Paper & 0.169 & 32 & 0.021 & 0.891 & 32 & 0.004 \\  & Monitor & 0.157 & 32 & 0.044 & 0.922 & 32 & 0.023 \\  & Oculus Quest 2 & 0.252 & 32 & 0.000 & 0.892 & 32 & 0.004 \\ \hline \multirow{3}{*}{Frustration} & Paper & 0.249 & 32 & 0.000 & 0.826 & 32 & 0.000 \\  & Monitor & 0.182 & 32 & 0.008 & 0.902 & 32 & 0.007 \\  & Oculus Quest 2 & 0.244 & 32 & 0.000 & 0.888 & 32 & 0.003 \\ \hline \multirow{3}{*}{Effort} & Paper & 0.299 & 32 & 0.000 & 0.805 & 32 & 0.000 \\  & Monitor & 0.178 & 32 & 0.011 & 0.849 & 32 & 0.000 \\ \cline{1-1}  & Oculus Quest 2 & 0.222 & 32 & 0.000 & 0.878 & 32 & 0.002 \\ \hline \end{tabular} Note.* * Lilliefors significance correction.  
\end{table} 
Table 3: Tests of normality. Based on the above experimental data, participants' mean (average) completion time shown in Figure 8 and error identification in Table 4 were calculated using the Kruskal-Wallis H test. Figure 8 compares the completion times between the three design review groups; Oculus Quest 2 group takes (17.49 min) to complete the task which is significantly less than other two groups, monitor-based and paper-based design task, which take (19.37 min) and (24.72 min), respectively. However, the average completion time of paper-based, monitor-based, and Oculus Quest 2-based groups (24.72, 19.37, and 17.49 min) and \(p\)-value less than 0.05 show a statistically significant difference. The Kruskal-Wallis H test examines these three groups' error identification, as shown in Table 4.  
The SART score was calculated by using Equation (1); when examined, the Oculus Quest 2 (12.34) had the highest cumulative score of SA, and monitor-based drawing had (12.0), and Oculus Quest 2 (10.00) had the lowest score. Lastly, statistically significant differences in the SA values of these three media (\(p<0.05\)) were analyzed.