## 3 Results and Discussion
### Human Factor
#### 3.2.2 Research Status  
Most scholars understand what the human factor refers to, its contents, and how to analyze these contents. However, it is unclear where the content boundary lies and what the differences are compared with the other two terms. Therefore, the contents studied by different scholars are not the same. The collected articles are listed in Table 3 based on the principle set out in Section 2.2. Their detailed information is provided in Appendix B. Among them, six articles (five journal articles and one conference paper) were review articles involving human factors, while the others were research articles. Notably, human-related factor [17], human influencing factor [20], and human contributing factor [37] were equal to human factor, according to the relevant articles. Research Article  
These articles often used newly proposed or modified models to conduct research. The popular model, HFACS, has many revised versions: HFACS-FFTA [38]; HFACS-PV [39; 40]; HFACS-Coll [41]; HFACS-MA [42], HFACS-BN [43]; and HFACS-PEHCA [44]. Different versions may produce different results, according to their research field. However, they all lie within the four categories of the framework: unsafe acts, preconditions for unsafe acts, unsafe supervision, and organization influences. [PERSON] et al. [45] used multidimensional association rules to explore the causation chains of human factors in ship accidents. Because this method comes under the framework of the reason model, the human factors are within four layers: organizational factors, organizational prevention and supervision, the premise of unsafe behavior, and unsafe behavior. [PERSON] et al. [46] proposed a structural equation-modeling technique with exploratory factor analysis and confirmatory factor analysis to identify human factors in seafaring. They identified five factors: situation awareness, adaptability, group skills, self-knowledge, and drive. Furthermore, [PERSON] et al. [47] proposed the card-sorting model, where human factors are classified into commercial pressure; the effect of environmental and external factors; improper design, installation, and working environment; inadequate leadership and supervision; lack of communication and coordination; lack of, improper, or late maintenance; lack of training; safety culture; safety management system; and unprofessional behavior. [PERSON] et al. [37] proposed an approach to determine the most important human factors in maritime accidents, collecting 94 contributing factors. They identified the top 10 factors but did not clarify whether the contributing factors can be equated to human factors. Excluding the top 10 human factors, it was ambiguous whether the remaining contributing factors were included. [PERSON] et al. [48] presented a dynamic Bayesian network (BN) combined with a pseudo fault tree to assess human factors. Three categories of human factors were identified: individual factor, organizational factor, and group factor. Furthermore, considering human factors, [PERSON] et al. [49] developed a BN-TRACEr model to quantitatively analyze ship operation risk. They identified 398 performance-shaping factors (PSFs), which were divided into six categories: aspects of communication/information; internal/external environment; organizational factors; training/competence; and personal factors. However, whether PSF equates to human factors remains unknown. [PERSON] et al. [50] developed a BN-TOPSIS model to explore maritime accident prevention strategies from the human factor perspective. They contributed to recommended prevention strategies but gave no information regarding the definition and scope of human factors. The same situation was found in other works [51; 52]. \begin{table}
\begin{tabular}{l c} \hline \hline
**Category** & **Number of Documents** \\ \hline Journal article & 30 \\ Conference paper & 11 \\ Dissertation & 2 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Collected articles with human factor in the title.