One of the difficulties arising when intercomparing remote sensing observations of atmospheric constituents profiles consists in homogenizing their respective vertical coordinates to allow quantitative results comparison. Simple profile interpolation is often unsatisfactory in this case, as the retrieval vertical grid constitutes an integral part of the retrieved vector which should be accounted for in subsequent profile transformations. Recently, a method of comparing remote sounders while allowing for different observational characteristics was proposed by Rodgers and Connor [1]. Unfortunately, application of this method was first restricted to the comparison of identical state vectors. We propose to relax this condition, by the use of a linear transformation function to homogenize the units and vertical grids of different retrievals results.