6. Measured glomerular filtration rate <80 mL/min/1.73 m2 calculated using the subject's measured serum creatinine and Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation1 or Modification of Diet in Renal Disease [MDRD] study estimation formula). Strict vegetarians (vegans) with a calculated GFR <70 mL/min/1.73m2 are excluded. The absolute (raw) GFR value will be used for subjects with body surface areas >1.73m2