1. Department of Nursing, Chungnam National University, Munhwaro 266, Junggu, Daejeon 35015, Republic of Korea
2. Korea Research Institute for Vocational Education & Training, Social Policy Building, Sejong National Research Complex, 370 Sicheong-daero, Sejong-si 30147, Republic of Korea
3. Department of Economics, Hongik University, Seoul 04066, Republic of Korea