A second box-end scoring artifact in the Farnsworth-Munsell 100-hue test.

PURPOSE To investigate and describe a hitherto unreported scoring artifact in the Farnsworth-Munsell 100-hue Test, arising from the grouping of the caps into four boxes, which causes caps near the ends of a box to score less than caps near the center of a box. This artifact is in addition to a previously reported one, which causes caps near the end of a box to score more than caps in the center of the box. METHODS Two different statistical simulations were used to generate synthetic cap sequences, which were scored in the normal way. RESULTS For error scores less than about 500, the new artifact, which depresses scores at the ends of boxes, was found to dominate the pattern of scores. CONCLUSION The existing published correction for the box-end scoring artifact is inappropriate for scores less than about 500, and therefore should be applied cautiously.