# Table 1 The expression of five equations basing on SCr in the study

Year Equation Name Equation
2009 CKD- EPI equation 141 × (SCr/0.9)−0.411 ×    0. 993Age(Male, SCr ≤ 0.9)
141 × (SCr/0.9)−1.209 × 0. 993Age(Male, SCr > 0.9)
144 × (SCr/0.7)−0.329 × 0. 993Age(Female, SCr ≤ 0.7)
144 × (SCr/0.7)−1.209 × 0. 993Age(Female, SCr > 0.7)
2011 LMR equation eX – 0.0158  Age + 0.438  In(Age)
X = 2.56 + 0.00968  (2 – SCr)(Male, Scr   < 2.0)
X = 2.56 – 0.926  In(SCr/2) (Male, Scr ≥ 2.0)
X = 2.50 + 0.0121  (1.7 – SCr) (Female, SCr  <  1.7)
X = 2.50 – 0.926  In (SCr/1.7) (Female, SCr ≥ 1.7)
2012 BIS1 equation 3736 × SCr−0.870 × age−0.950 × (0.82 Female)
2016 FAS equation 107.3/(SCr/0.9) × [0. 988(age − 40)age > 40 years](Male)
107.3/(SCr/0.7) × [0. 988(age − 40)age > 40 years](Female)
2020 EKFC equation 107.3 × (SCr/0.9)−0.322 × [0.990(age − 40)age > 40 years] (Male, SCr  <  0.9)
107.3 × (SCr/0.9)−1.132 × [0.990(age − 40)age > 40 years] (Male, SCr ≥ 0.9)
107.3 × (SCr/0.7)−0.322 × [0.990(age − 40)age > 40 years](Female, SCr <  0.7)
107.3 × (SCr/0.7)−1.132 × [0.990(age − 40)age > 40 years] (Female, SCr ≥ 0.7)
1. Abbreviations: Scr (mg/dl) Serum creatinine, CKD-EPI Chronic kidney disease epidemiology collaboration, LMR Lund-Malmö Revised, BIS1 Berlin Initiative Study 1, FAS Full age spectrum equation, EKFC European Kidney Function Consortium. serum creatinine expressed as mg/dl while 1 mg/dl equal to 88.4 μmol/l 