# Improvements of Design for Safety in Construction through Multi-Participants Perception Analysis
## 4 Results and Discussion  
### Absolute Importance of the DfS Improvement Alternatives from the Overall Respondents' Perspective  
In the chapter entitled \"Conduct of the Questionnaire Survey,\" based on the results of the questionnaire survey, the absolute importance of the eight DfS improvement alternatives is presented. Table 6 and Figure 3 present the absolute importance of the eight DfS improvement alternatives according to the construction project participants and career levels, as perceived by the respondents. As mentioned earlier, the respondents overall judged that DfS improvements are needed, as the value of their perceived absolute importance of the eight DfS improvement alternatives was 3.745. For the DfS participants, the researchers, among all construction project participant respondents in this study, accorded utmost importance to the DfS improvement alternatives, with a 4.100 absolute importance value, possibly because researchers have performed various studies to improve DfS [15; 28; 43] and have come to recognize the importance of DfS in reducing the accident rate in the construction industry. The researchers were followed by the contractors and designers, with absolute importance values of 4.016 and 3.675, respectively. Recognizing the need for DfS improvements, the contractors and the designers also judged that the eight DfS improvement alternatives are important because they are the ones who actually implement DfS. Conversely, the clients and the construction managers, who are responsible for DfS, did not accord much importance to the eight DfS improvement alternatives. In terms of the career level, the respondents overall with experience of less than ten years and those with experience of more than ten years thought highly of the DfS improvement alternatives, with absolute importance values of 3.597 and 3.819, respectively. Therefore, the respondents with higher career levels felt the limitations of safety management in the construction phase and emphasized the importance of DfS for safety management in the design phase.  
Figure 2: Result of absolute importance of alternatives.  
\begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline  & **Overall** & **Client** & **Designer** & **Contractor** & \begin{tabular}{c} **Construction** \\ **Manager** \\ \end{tabular} & **Researcher** & \
\begin{tabular}{c} **Experienced** \\ **under 10 Years** \\ \end{tabular} &
\begin{tabular}{c} **Experienced** \\ **over 10 Years** \\ \end{tabular} \\ \hline Application of extended coverage & 3.407 & 2.400 & 3.400 & 3.750 & 3.333 & 4.000 & 3.000 & 3.611 \\ Adjustment of the application phase & 3.852 & 2.800 & 3.800 & 4.125 & 3.667 & 4.200 & 3.889 & 3.833 \\ Application of the design alternative & 3.630 & 3.000 & 3.800 & 4.125 & 3.000 & 3.400 & 3.556 & 3.667 \\ Development of a collaboration program & 3.852 & 3.400 & 3.800 & 4.250 & 2.667 & 4.000 & 3.556 & 4.000 \\ Development of a training program for experts & 3.704 & 3.200 & 3.200 & 3.625 & 3.333 & 4.400 & 3.444 & 3.833 \\ Involvement of the contractor in & 3.926 & 2.800 & 3.400 & 4.750 & 3.667 & 4.200 & 3.556 & 4.111 \\ The pre-constration phase & 3.67 & 2.800 & 3.800 & 3.625 & 3.667 & 4.000 & 4.111 & 3.444 \\ Development of a decision support system & 3.926 & 3.000 & 4.200 & 3.875 & 3.667 & 4.600 & 3.667 & 4.056 \\ Assignment of responsibility for DIS to the client & 3.926 & 3.000 & 4.200 & 3.875 & 3.667 & 4.600 & 3.667 & 4.056 \\ \hline AVG & 3.745 & 2.925 & 3.675 & 4.016 & 3.375 & 4.100 & 3.597 & 3.819 \\ \hline \hline \end{tabular}
\end{table}
Table 6: Results of the absolute importance of the DIS improvement alternatives.