Affiliation: | a Department of Nursing, National Taiwan University, 1 Jen-Ai Rd., Section 1, Taipei 100, Taiwan, ROC b College of Medicine, National Taiwan University, 1 Jen-Ai Rd., Section 1, Taipei 100, Taiwan, ROC c Institute of Statistics, National Chiao Tung University, 1001 Ta Hsueh Road, Hsinchu 300, Taiwan, ROC |