In June 2010, the IFCC Working Group successfully developed a reference material (ERM-DA471 / IFCC) for measuring serum cystatin C, and in collaboration with major diagnostic companies, formulated a globally applicable GFR prediction equation based on cystatin C. The accuracy of the 2012 cystatin C equation is similar to the 2009 creatinine equation, but it avoids racial factors. Professor Michelle M. Estrella believes that compared to creatinine, CysC is less affected by non-renal factors.