A norm-referenced test is one that is designed to facilitate interpretations of scores by comparing scores based on the ordering of examinees within a well-defined group of interest. Two important definitions associated with norm-referenced interpretations are percentiles and percentile ranks. A percentile is a test score below which falls a certain percentage of the scores. A percentile rank is the percentage of people who have a score lower than the score of interest.

Since about 1905, norm-referenced interpretations have been a dominant approach to making test scores meaningful to both educators and the public, although criterion-referenced interpretations have been gaining in prominence over the past several decades. A special type of criterion-referenced interpretation, known as standards-based interpretation, has been gaining in popularity since No Child Left ...