###### Abstract
The results from 43 patients showed significant improvements in the functional, physical, and emotional subscale scores of the VHI before and after surgery. Postoperative VHI scores had weak correlations with other voice measurements, but preoperative VHI scores were the only significant predictive variable; therefore, the results of this study demonstrate that VHI is an important tool for assessing treatment outcomes in UVFP patients [14]. [PERSON] et al. used multivariate analysis of variance (MANOVA) to compare the VHI scores between groups with structural and functional voice disorders. The results showed that patients with structural voice disorders had significantly higher VHI scores than those with functional voice disorders; therefore, this paper is significant in that the authors evaluate the severity of voice disorders according to each type and propose appropriate treatment methods [15]. [PERSON] et al. analyzed the association between the VHI and Praat voice analysis in patients with benign vocal cord lesions before and after microscopic laryngeal surgery. The results of this study demonstrate a significant correlation between the total VHI score and jitter, as well as between the functional subscale score and HNR after surgery [16]. The above findings indicated that the VHI has proven to be an important assessment tool in various voice disorders and treatment situations, including vocal fold polyp treatment, arytenoid adduction surgery for patients with unilateral vocal fold paralysis, the evaluation of structural and functional voice disorders, microscopic laryngeal surgery for benign vocal cord lesions, etc. Notably, the VHI has shown correlations with specific acoustic parameters; overall, it demonstrates its significance as a meaningful indicator for evaluating treatment outcomes in patients with various voice disorders [13; 14; 15; 16; 17]. However, these studies focus on analyzing the correlations between acoustic parameters and VHI scores using \(p\)-values. Additionally, some studies have centered on correlation analysis with only the total VHI score; thus, the first limitation of these studies is the limitation of correlation analysis. Correlation analysis does not establish causation, and relying on \(p\)-values may not adequately reflect the clinical significance of the findings. Secondly, in most studies, researchers have analyzed the significant relationships between objective acoustic parameters and the AHI. These constraints have compromised the reliability of outcomes in earlier studies, contributing to a limited and fragmented comprehension of speech treatment. In order to address these limitations in this study, we aim to conduct a comprehensive analysis of predictive factors related to personal habits that influence speech therapy outcomes, as measured using the VHI; in particular, we examine significant relationships and predictive factors, not only in relation to the total VHI score, but also across its functional, physical, and emotional subdomains. We utilize a range of methodologies to achieve these objectives, including assessments of personal characteristics, statistical analysis, logistic regression, random forest, and a multilayer perceptron model. Through this multifaceted approach, we seek to elucidate the correlations between predictive factors and VHI outcomes, encompassing the functional, physical, and emotional scores. The findings of this research are anticipated to offer valuable insights for clinicians and speech-language therapists, particularly in the context of the VHI; moreover, the development of personalized treatment strategies as informed by these predictive factors has the potential to significantly enhance the efficacy of speech therapy and improve both vocal function and quality of life for individuals with speech disorders.