Entry criteria for RCTs involving Table 1 | Relationship among categories for albuminuria and proteinuriaa Categories Measure Normal to mildly increased Moderately increased Severely increased ACR PCR Protein reagent strip Negative to trace Trace to + + or greater ACR, albumin/creatinine ratio; AER, albumin excretion rate; PCR, protein/creatinine ratio, PER, protein excretion rate. Albuminuria and proteinuria can be measured using excretion rates in timed urine collections, ratio of concentrations to creatinine concentration in spot urine samples, and using reagent strips in spot urine samples. Relationships among measurement methods within a category are not exact. The relationships between AER and ACR and between PER and PCR are based on the assumption that average creatinine excretion rate is approximately 1.0 g/24 h or 10 mmol/24 h. The conversions are rounded for pragmatic reasons. (For an exact conversion from mg/g of creatinine to mg/mmol of creatinine, multiply by 0.113.) Creatinine excretion varies with age, sex, race and diet; therefore the relationship among these categories is approximate only. ACR o10 mg/g (o1 mg/mmol) is considered normal; ACR 10 29 mg/g (1.0 2.9 mg/mmol) is considered high normal. The relationship between urine reagent strip results and other measures depends on urine concentration. a Tentatively adopted by KDIGO CKD Work Group. CKD patients are usually based on these parameters, changes in which may form the basis for kidney end points. Kidney function. Changes in kidney function are impor- tant outcomes in clinical trials assessing the effects of various BP-management regimens in CKD patients. Although the most important events are the requirement for renal replacement therapy or death due to kidney failure, many studies have used surrogates such as changes in GFR or the percentage of patients in whom the serum creatinine (SCr) level doubles. 