## 5 Data Analysis
### Questionnaire Result  
One hundred thirty randomly selected subjects filled out the self-measurement driving behavior survey. These subjects were divided into two groups according to their questionnaire scores (60 subjects belonged to the high driving fear score group, 61 belonged to the lower score group, and 9 were excluded due to incomplete answers). Thirty of the sixty subjects in a waiting queue that belonged to the high driving fear score group were randomly selected and assigned to treatment group (TG) to participate in the VRET experiment. Subjects from the low driving fear group were used as the control group (CG). A \(t\)-test measured the difference between the means of driving behavior questionnaire scores for the TG and CG. The behavior scores were significantly different (95% confidence interval = (51.7, 66.12); \(p\)-value = 0.000). Subjects in the TG completed the same self-measurement driving behavior survey after the VRET experiment to measure the effectiveness of the experiment. The hypothesis is that the subjects' driving anxiety is reduced through VRET and their subjective distress is reduced toward the level of the CG that had significantly lower driving fear scores. Table 2 presents the means and standard deviations (SDs) of each question in the survey, compared between TG's pre-treatment questionnaire score (TG pre), TG's post-treatment questionnaire score (TG post), and the CG's questionnaire score (CG) without treatment. The SDs of all survey question results showed no significant differences between TG pre, TG post, and CG using a one-way ANOVA test. A one-way ANOVA test was used to compare three mean scores (i.e., TG pre, TG post, and CG) for the 39 questions. A 95% confidence interval (CI) with pairwise comparisons detect there were significant differences between the means of the scores. [PERSON]'s least significant difference method for multiple comparisons was applied to examine the means for different groups (Figure 7). The results of multiple comparisons show that there were significant differences between all pairs (i.e., TG pre vs. TG post, TG pre vs. CG score, TG post vs. CG score). The ANOVA tests support significant evidence that the TG's subjective distress was reduced through the treatment of VRET. The fear reduction (TG post) was not reduced to the same level as that of the control group. The experiment demonstrates with high confidence that the driving phobia VRET system can effectively reduce the subject's avoidance of driving to a significant degree, but there is still a gap for complete recovery. Further analysis on different types of questionnaire designs from the American Psychological Association and other international organizations will be studied for future implementation. The questionnaire design is based on three driving-behavior-survey studies, Q1-Q19 refer to an anxious driving behavior study [12], Q20-Q32 refer to a DRAS mentioned in one anxiety-related-avoidance research [13], and Q33-Q39 focus on driving in specific environments or conditions [14]. A one-way ANOVA tests and [PERSON]'s least significant difference model for multiple comparisons are applied to each questionnaire design (Figure 8a-c). The ANOVA analysis results relate to the questionnaire design for anxious driving behavior and anxiety-related-avoidance (Q1-Q32) from previous peer reviewed studies. The TG's post-treatment questionnaire scores are significantly lowered after participating in the VRET experiment, though the results are still higher than the CG's questionnaire scores. The result of the questionnaire design, which relates to driving in specific environments (Q33-Q39), shows that there are no significant differences between the TG post-treatment scores and the CG scores.