A method of determining a number of a solution constituent comprising: introducing a first number of solution constituents to a first test location; creating a first residual number of solution constituents by binding a first plurality of solution constituents at the first test location wherein the first plurality of solution constituents includes a first portion of a first solution constituent and a first portion of a second solution constituent, said first solution constituent being an analyte of interest and said second solution constituent being an interfering analyte featuring cross reactivity with said first test location; creating a second residual number of solution constituents by binding a second plurality of solution constituents from the first residual number of solution constituents wherein the second plurality of solution constituents includes a second portion of the first solution constituent and a second portion of the second solution constituent; obtaining a first signal associated with the bound first plurality of solution constituents; obtaining a second signal associated with the bound second plurality of solution constituents; and determining a second number of the first solution constituent based upon the obtained first signal and the obtained second signal, wherein the obtained first signal and the obtained second signal are used to compensate for the second solution constituent and wherein determining a second number of the first solution constituent comprises determining the second number based upon the following equations: S 1 = a 1 − 1 n 1 − 1 + a 1 − 2 n 1 − 2 + ⋯ a 1 − x n 1 − x S 2 = a 2 − 1 n 2 − 1 + a 2 − 2 n 2 − 2 + ⋯ a 2 − x n 2 − x wherein "S 1 " is the first signal, "S 2 " is the second signal, "a 1-1 " is a known percentage (a) of a solution constituent (1 through x) which binds at the first test location, "n 1-1 " is a number (n) of the solution constituent (1 through x) at the first test location, "a 2-1 " is a known percentage (a) of a solution constituent (1 through x) which binds at a second test location, and "n 2-1 " is a number (n) of the solution constituent (1 through x) at the second test location. introducing a first number of solution constituents to a first test location; creating a first residual number of solution constituents by binding a first plurality of solution constituents at the first test location wherein the first plurality of solution constituents includes a first portion of a first solution constituent and a first portion of a second solution constituent, said first solution constituent being an analyte of interest and said second solution constituent being an interfering analyte featuring cross reactivity with said first test location; creating a second residual number of solution constituents by binding a second plurality of solution constituents from the first residual number of solution constituents wherein the second plurality of solution constituents includes a second portion of the first solution constituent and a second portion of the second solution constituent; obtaining a first signal associated with the bound first plurality of solution constituents; obtaining a second signal associated with the bound second plurality of solution constituents; and determining a second number of the first solution constituent based upon the obtained first signal and the obtained second signal, wherein the obtained first signal and the obtained second signal are used to compensate for the second solution constituent and wherein determining a second number of the first solution constituent comprises determining the second number based upon the following equations: S 1 = a 1 − 1 n 1 − 1 + a 1 − 2 n 1 − 2 + ⋯ a 1 − x n 1 − x S 2 = a 2 − 1 n 2 − 1 + a 2 − 2 n 2 − 2 + ⋯ a 2 − x n 2 − x wherein "S 1 " is the first signal, "S 2 " is the second signal, "a 1-1 " is a known percentage (a) of a solution constituent (1 through x) which binds at the first test location, "n 1-1 " is a number (n) of the solution constituent (1 through x) at the first test location, "a 2-1 " is a known percentage (a) of a solution constituent (1 through x) which binds at a second test location, and "n 2-1 " is a number (n) of the solution constituent (1 through x) at the second test location. "S 1 " is the first signal, "S 2 " is the second signal, "a 1-1 " is a known percentage (a) of a solution constituent (1 through x) which binds at the first test location, "n 1-1 " is a number (n) of the solution constituent (1 through x) at the first test location, "a 2-1 " is a known percentage (a) of a solution constituent (1 through x) which binds at a second test location, and "n 2-1 " is a number (n) of the solution constituent (1 through x) at the second test location.