Useful documentation for this comparison can be found on p. 1 of Gabriel Danovitch, 'Handbook of Kidney Transplantation' (Philadelphia: Lippincott, 2001), where he states that "the most efficient hemodialysis regimens currently provide only 10% tp 12% of the small solute removal achieved by two normally functioning kidneys."  This comment should be updated, however, by reference to data from the new programs of short- and long-daily home hemodialysis performed six days or nights a week, which improve solute clearance, although still fall far short of achieving what normal kidneys can do. User: JP Marat