Prevalence of Vitamin D Deficiency and Associated Factors in Critically Ill Patients: A Multicenter Observational Study oleh Kuo-Wei Chen, Chung-Wei Chen, Kuo-Ching Yuan, I-Ting Wang, Fang-Ming Hung, An-Yi Wang, An-Yi Wang, An-Yi Wang, Yin-Chin Wang, Yu-Ting Kuo, Yi-Che Lin, Ming-Chieh Shih, Yu-Chung Kung, Sheng-Yuan Ruan, Ching-Tang Chiu, Anne Chao, Yin-Yi Han, Li-Kuo Kuo, Li-Kuo Kuo, Yu-Chang Yeh