 creatinine clearance estimation by Schwartz formula (Schwartz), serum creatinine (Cr), serum cystatin C, and serum beta0-microglobulin (B0M) in patients with renal dysfunction (CrC less than 00 ml/minute per 0.00 m^0^) and normal renal function are shown. CI, confidence interval; N, number of patients; NS, not significant.  ######   Comparison of groups with creatinine clearance estimation by Schwartz formula lower and higher than 00 ml/minute per 0.00 m^0^                              