calculated renal blood flow rate absolute change in renal blood flow rate 2012-10-15T11:59:32Z JSmith The difference in the volume of blood delivered to or exiting from the kidneys per unit time between two points in time or two conditions expressed as the result of the subtraction in and of itself without comparison by ratio with another quantity. The term "absolute change" refers to the subtraction of one value from another, as opposed to a dissimilarity of two values expressed as a ratio or as a percentage. In this context it is not intended to necessarily imply the difference expressed as an absolute value |n|, that is, the numeric value of the difference without regard to its sign.