GFR is just a calculation. You put in your age, gender etc.... So I don't think she is correct.Try it here: http://www.davita.com/gfr-calculator/
Needed to know my GFR (Glumerular Filtration Rate) other than inquiring in the dialysis center.For any that may be interested:http://www.clinicalculator.com/english/nephrology/cockroft/cca.htm