## 3 Results
### Descriptive Analyses and Study of Covariates  
Table 1 shows the statistically significant positive correlations between pain anticipation, dental anxiety, and subjective avoidance (all \(p\) < 0.001). The largest effect size was observed in the case of the correlation between pain anticipation and dental anxiety, followed by subjective avoidance and dental anxiety. Significant negative correlations were also found between dental anxiety and positive affect (\(p\) = 0.004) and between pain anticipation and positive affect (\(p\) = 0.011). Regarding the possible covariates considered (previous medication, radiolucent apical lesion, ASA-PS Classification, number of canals, pulpal diagnosis, AAE Endodontic Case Difficulty Assessment Form), significant associations were only observed in the case of medication prior to treatment and pain anticipation. Specifically, the fact that patients were (or were not) taking medication prior to starting root canal treatment maintained significant \begin{table}
\begin{tabular}{c c c c c} \hline  & **Mean (SD)** & **2** & **3** & **4** \\ \hline
1. Pain anticipation & 4.11 (2.40) & 0.581 ** & 0.386 ** & \(-\)0.253 * \\
2. Dental anxiety & 10.29 (4.79) & & 0.411 ** & \(-\)0.284 ** \\
3. Subjective avoidance & 4.75 (3.53) & & & \(-\)0.065 \\
4. Positive affect & 35.72 (5.09) & & & \\ \hline \end{tabular}
\end{table} 
Table 1: Mean, standard deviation and correlation between outcome variables. associations with pain anticipation and was closely related to significance with dental anxiety (\(p\) = 0.007). Specifically, patients who took prior medication had significantly higher pain anticipation scores (Mean = 5.28, SD = 2.08) than those who were not taking prior medication (Mean = 3.63, SD = 2.38), (\(t\) = \(-\)3.401, \(p\) = 0.001, partial eta squared = 0.096). The Moderation Mediation Model of Pain Anticipation on Subjective Avoidance by Dental Anxiety, at Different Levels of Positive Affect  
2.1 Previous Analysis: Mediation Role of Dental Anxiety between Pain Anticipation and Subjective Avoidance  
Conforming to the purpose of this research, the mediation role of dental anxiety between pain anticipation and subjective avoidance was analyzed, controlling for medication prior to endodontic treatment (covariate). The findings show that dental anxiety significantly mediated the association between pain anticipation and subjective avoidance (bootstrap CI greater than zero) when controlling for previous medication. The model shows a significant total effect (c = 0.570, \(t\) = 3.93, \(p\) < 0.01, [95% CI = 0.283/0.858]). The direct effects of pain anticipation on dental anxiety were observed (\(\beta\) = 1.16, SE = 0.17; \(t\) = 6.69, \(p\) < 0.001, [95% CI = 0.822/1.516]); as well as effects in dental anxiety on subjective avoidance (\(\beta\) = 0.206, SE = 0.08; \(t\) = 2.506, \(p\) = 0.013; [95% CI = 0.042/0.370]). The direct effect of pain anticipation on subjective avoidance was close to significance (c = 0.329, \(t\) = 1.92, \(p\) = 0.057, [95% CI = \(-\)0.010/0.668]). The overall model allowed the explanation of a 20% (F = 7.99; \(p\) < 0.0001) variance in subjective avoidance. 2.2 The Moderation Mediation Model of Pain Anticipation on Subjective Avoidance by Dental Anxiety at Different Levels of Positive Affect  
Based on previous results, the indirect effect of pain anticipation on subjective avoidance was examined through dental anxiety as a function of the levels of positive affect. Previous medication was included as a covariate. The results show that the effect of pain anticipation on dental anxiety depends on the levels of positive affect after including the effect of covariates (i.e., previous medication). Although in the three levels of positive affect, the relationship was statistically significant, it decreased when the positive affect was greater.