The tool used here to measure SQOL was the Korean language version of SQOL by [30]; modified from the original SQOL devel- oped by [31] to suit the Korean culture. The tool of this study uses a 6-point Likert scale and has 18 questions. Scores on this tool range from 18 to 108 points, with higher scores indicating higher levels of SQOL. The Cronbach's alpha for the previous study was .87 [30], and that of the current study was .91.