Method for determining the cleaning effectiveness of toilet paper

A method for determining the effective cleaning of bath tissue. The method can include providing at least one pair of worn underwear; optionally, cutting the pair of worn underwear and laying it flat with the inside surface exposed; scanning an image of the exposed, inside surface of the underwear, the image including at least a portion of the underwear likely to have fecal staining; capturing with the image at least one color standard; selecting image points in areas of the scanned image visually appearing clean and areas of the scanned image visually appearing stained with fecal staining; optionally, converting the Red, Green, Blue (RGB) color to L*a*b* color values; utilizing analysis software to characterize other areas of the scanned image corresponding to image points having similar color to the image points selected as clean or stained with fecal staining; classifying the entire image, pixel by pixel, into defined portions of the underwear that are clean or stained with fecal staining; and, calculating areas corresponding to portions of the underwear stained with fecal staining.