The Comprehensive Test of Phonological Processing (CTOPP) measures reading related to phonological skills and provides the examiner with a comparative index of phonological processes strengths and weaknesses. The CTOPP is short enough that there is no fatigue factor. The population sample for standardization includes a broad spectrum of Americans.

The Comprehensive Test of Phonological Processing (CTOPP) assesses phonological awareness, phonological memory, and rapid naming. Persons with deficits in one or more of these kinds of phonological processing abilities may have more difficulty learning to read than those who do not. The CTOPP was developed to aid in the identification of individuals from kindergarten through college who may profit from instructional activities to enhance their phonological skills. Because the test battery spans such a wide range of ages, and the abilities it taps are so varied across the ages, it was necessary to develop two versions of the test. The first version, developed for individuals ages 5 and 6 (primarily kindergartners and first graders), contains seven core subtests and one supplemental test. The second version, for individuals ages 7 through 24 (persons in second grade through college), contains six core subtests and eight supplemental tests. In both versions, the supplemental tests are provided to allow the examiner to more carefully assess specific phonological strengths and weaknesses. Both versions are individually administered, taking about 30 minutes to administer the core subtests.

Percentiles, standard scores, and age and grade equivalents are provided. Percentiles are easily understood by parents and others with whom the examiner might want to share the results. Subtest standard scores have a mean of 10 and a standard deviation of 3. The Phonological Awareness, Phonological Memory, and Rapid Naming quotients have a mean of 100 and a standard deviation of 15. Age and grade equivalents show the relative standing of individuals' scores.

The CTOPP was normed on over 1,600 individuals ranging in age from 5 through 24 and residing in 30 states. Over half of the norming sample came from children in elementary school (through grade five), where the CTOPP is expected to have its widest use. The demographic characteristics of the normative sample are representative of the U.S. population as a whole with regard to gender, race, ethnicity, residence, family income, educational attainment of parents, and geographic regions. The sample characteristics were stratified by age and keyed to the demographic characteristics reported in the 1997 Statistical Abstract of the United States.

Reliability of the CTOPP was investigated using estimates of content sampling, time sampling, and scorer differences. Most of the average internal consistency or alternate forms reliability coefficients (content sampling) exceed .80. The test/retest (time sampling) coefficients range from .70 to .92. The magnitude of the coefficients reported from all the reliability studies suggests that there is limited error in the CTOPP and that examiners can have confidence in the results.