The ungraded recommendations are generally written as simple declarative statements, but are not meant to be interpreted as being stronger recommendations than Level 1 or 2 recommendations. NOMENCLATURE AND DESCRIPTION FOR RATING GUIDELINE RECOMMENDATIONS Within each recommendation, the strength of recommendation is indicated as Level 1, Level 2, or Not Graded, and the quality of the supporting evidence is shown as A, B, C, or D. Reference Keys Kidney International Supplements (2013) 3, vii vii http://www.kidney-international.org & 2013 KDIGO CURRENT CHRONIC KIDNEY DISEASE (CKD) NOMENCLATURE USED BY KDIGO CKD is defined as abnormalities of kidney structure or function, present for 43 months, with implications for health. CKD is classified based on Cause, GFR category (G1-G5), and Albuminuria category (A1-A3), abbreviated as CGA. Persistent albuminuria categories Description and range Normal to mildly increased Moderately increased Severely increased GFR categories (ml/min/ m ) Description and range G1 Normal or high 90 Mildly to moderately decreased Moderately to severely decreased Prognosis of CKD by GFR and Albuminuria Categories: Prognosis of CKD by GFR and albuminuria category Green: low risk (if no other markers of kidney disease, no CKD); Yellow: moderately increased risk; Orange: high risk; Red, very high risk. http://www.kidney-international.org & 2013 KDIGO viii Kidney International Supplements (2013) 3, viii CONVERSION FACTORS OF CONVENTIONAL UNITS TO SI UNITS Parameter Conventional unit Conversion factor SI units Cholesterol (total, HDL-C, LDL-C) mg/dl 0.0259 mmol/l Creatinine (serum, plasma) mg/dl 88.4 mmol/l Triglycerides (serum) mg/dl 0.0113 mmol/l Abbreviations: HDL-C, high-density lipoprotein cholesterol; LDL-C, low-density lipoprotein cholesterol. Note: Conventional unit  conversion factor SI unit. 