15947
RESEARCH DESIGN AND METHODS In a historical prospective cohort study of subjects from the Clalit Health Services database , which includes information on nearly 4 million people , diabetes - free subjects aged 40 - 70 years with serum 25 - hydroxycholecalciferol ( 25 - OHD ) measurements available were followed for 2 years to assess the development of IFG and diabetes in five 25 - OHD subgroups : >= 25 , 25 . 1 - 37 . 5 , 37 . 6 - 50 , 50 . 1 - 75 , and > 75 nmol / L .
 25 - hydroxycholecalciferol, 25 - OHD, 25 - OHD
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 25 - hydroxycholecalciferol, 25 - OHD, 25 - OHD