Comprehensive Test of Phonological Processing-Second Edition CTOPP-2

Original Editor - Vidya Acharya
Top Contributors - Vidya Acharya and Alexandra Stead

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Introduction

The Comprehensive Test of Phonological Processing-Second Edition (CTOPP-2) is a norm-referenced test designed to measure the phonological processing skills of individuals aged 4 years to 24 years and 11 months. Wagner and colleagues developed the Comprehensive Test of Phonological Processing (CTOPP) in 1999 to assess the phonological processing skills of individuals ages 5 to 24 years. CTOPP-2 is based original CTOPP but has expanded its age range, providing assessment versions for children aged 4 to 6 years and for individuals aged 7 to 24 years and 11 months.

Phonological processing

Reading comprehension requires both language and phonological processing abilities. Phonological processing is the ability to utilise the phonological information, that is, sounds of one's language when processing both written and oral language. Several terms are associated with phonological processing, which includes speech processing, phonological awareness, phonemic awareness, decoding, and, auditory processing. Overall, phonological processing measures the following components:

• speech discrimination: the ability to discriminate sounds.

• decoding: the ability to recognise written words correctly, which facilitates access to the mental lexicon and aids in retrieving semantic information at the word level.
• phonological awareness: the ability to recognise and manipulate sounds in spoken language, including words, syllables, onsets, and rimes.
• phonemic awareness: is the understanding that spoken language is made up of phonemes, assessed by asking about the phonemic structure of words and syllables.

Assessing phonological processing abilities is important when there are concerns regarding reading difficulties.

Purpose

CTOPP-2 is an essential assessment tool for speech and language pathologists, clinical psychologists, school psychologists, and educational professionals. It can:

• identify individuals, particularly kindergarten and first graders, who are significantly below their peers in phonological processing abilities and at risk of developing reading difficulties, facilitating early intervention or prevention services.
• track progress in response to various intervention methods
• give valuable insights into child’s relative strengths and weaknesses to explain challenges and guide support strategies
• serve as a measurement tool in research studies investigating phonological processing

Technique

Administration

Time: Administration of the entire test for each group takes approximately 40 minutes.

Materials needed: the picture book, examiner record booklet, the CD, a CD player, a stopwatch, pencil with an eraser.

Feedback is given to the examinee during the administration of the initial items to ensure that the examinee has mastered the task.

Test Construction/Format

The test materials are user-friendly and well-designed, featuring abbreviated instructions and practice items for easy administration. The manual offers clear guidelines for administering and scoring each subtest, as well as details on reliability, validity, and normative data. CTOPP-2 includes 5 composite and twelve subtests plus supplemental tests. The assessment for 4 to 6 years old version contains nine core subtests and one supplemental subtest, while the assessment for  7 to 24 years old  contains seven core subtests and two supplemental tests. The five composites are:

Phonological Awareness (PA)

This score represents awareness of and access to the phonological structure of oral language. This comprises the following subtests:

• Elision: (all ages) the examinee listens to a word, repeats it, and then is asked to say the word without a designated sound (e.g., “Say cat without the /c/”)
• Blending Words:(all ages) the examinee listens to a series of audio-recorded separate sounds and then is asked to blend them together to make a whole word (e.g., “What do these sounds make: b-oi?” The correct response is “boy.”).
• Sound Matching (4 to 6 years): the examiner says a word, pauses, and then says three other words while pointing to drawings that represent all four words
  • For the first 13 items, examiner asks the examinee to point to the picture that has the same initial sound as the word the examiner provides (e.g., “Which word starts with the same sound as pig? Pan, cat, or dog?” The correct response is “pan.”).
  • For the remaining 13 items, the examinee is asked to point to the picture that has the same final sound as the word the examiner provides.

• Phoneme Isolation ( 7 to 24 year old): the examinee is asked to identify the first and last sounds of words (for e.g., “what is the first sound in the word mop?”), middle sounds and other parts of words made up of more sounds (e.g., “what is the third sound in the word stop?”)

Phonological Memory (PM)

This helps to measure the ability to code information phonologically for temporary storage in working or short-term memory. This is comprised of the below subtests for all the ages:

• Memory for Digits (all ages): the examinee listens to an audio recording of numbers and is asked to repeat them.
• Nonword Repetition (all ages): the examinee listens to an audio recording of non-words and is asked to repeat them.

Rapid Symbolic Naming (RSN)

This composite score measures the ability to include efficient retrieval of phonological information from long-term or permanent memory and execute a sequence of operations quickly and repeatedly. It consists of the subtests applicable for all age groups:

• Rapid Digit Naming (all ages): the examinee is asked to quickly name the numbers on each row from left to right until all the numbers have been named
• Rapid Letter Naming (all ages): the examinee is asked to quickly name the letters on each row from left to right until all the letters have been named.

Rapid Non-symbolic Naming (RNN)

This composite score measures the ability to include efficient retrieval of phonological information from long-term or permanent memory and execute a sequence of operations quickly and repeatedly using objects and colours. This composite is for the 4 to 6 year olds and consists of the following subtests:

• Rapid Colour Naming (4- to 6-year olds): the examinee is asked to quickly name the colours on each row from left to right until all the colours have been named
• Rapid Object Naming (4 to 6 year olds): the examinee is asked to quickly name drawings of objects (e.g., star, key) on each row from left to right until all the objects have been named.

Alternate Phonological Awareness (APA)

This supplemental composite for measuring phonological awareness, is available for 7 through 24 year olds. It measures phonological awareness exclusively with nonwords, memory, as well as the ability to execute a sequence of operations quickly and repeatedly. It is comprised of the following subtests:

• Blending Nonwords (7 to 24 year olds): the examinee listens to a series of audio-recorded separate sounds and then is asked to blend the sounds together to make a nonword
• Segmenting Nonwords (7 to 24 year olds): the examinee listens to an audio-recorded nonword, repeats the nonword, and then says it one sound at a time.

Test Scores and Interpretation

For untimed subtests (i.e., Elision, Blending Words, Sound Matching, Phoneme Isolation, Blending Nonwords, Segmenting Nonwords, Memory for Digits, and Nonword Repetition), test begins with Item 1 for all the examinees, regardless of age. Examinee receives 1 point for each correct answer and 0 points for incorrect ones until they attempt three consecutive incorrect answers. Testing stops and no score is given if they fail to answer any of the first three items correctly, even after feedback.

For the timed subtests (i.e., Rapid Digit Naming, Rapid Letter Naming, Rapid Object Naming, and Rapid Color Naming), the examinee's score depends upon the time taken (number of seconds) to complete the task. The examiner proceeds to the next item if the examinee hesitates for more than 2 s on any item. Testing is discontinued and no score is recorded if the examinee cannot correctly name all of the items (i.e., the letters, numbers, colors, or objects) after error correction during the practice or makes four or more naming errors during the subtest. Mastering items in the practice session is crucial because the timed subtests measure the speed with which examinees can name symbolic or non-symbolic items, not knowledge of the items.

The CTOPP-2 provides six types of normative scores: age equivalents, grade equivalents, percentile ranks, subtest scaled scores, composite indexes, and developmental scores:

• The subtest scaled scores have a mean of 10 and a standard deviation of 3.
• The composite score indexes have a mean of 100 and a standard deviation of 15.
• The CTOPP-2 has a new Rasch-based developmental score available for the untimed subtests. It provides an equal-interval scale for monitoring performance changes over time with developmental scores linked with raw scores having approximately equal intervals, indicating successful scaling.
• Age and grade equivalents indicate the relative standing of individuals' scores. The test authors also recommend that examiners use scaled scores, composite scores, and percentile ranks when reporting results, in accordance with professional standards. They provide explanation for determining statistically significant discrepancies at a .05 level of confidence between subtest and composite scores.
• The authors recommend using composite scores for diagnosis and placement, and subtest scores to identify individuals’ strengths and weaknesses. The CTOPP-2 examiner’s manual states that test scores may contribute to selecting long-term educational goals, but scores should not be used for planning daily instruction programs.

Evidence

Standardisation

The CTOPP-2 was standardised on a normative sample of 1,900 individuals aged 4 to 24 years across six U.S. states. Demographic data were stratified by age and matched against 2010 U.S. Census data, establishing a nationally representative sample for general use in United States.

Floor and Ceiling effects

Several CTOPP-2 subtests exhibit insufficient floors at the earliest ages and insufficient ceilings at the later ages. Floor effect means the easiest items are still too hard for the youngest examinees, and ceiling effect means the hardest items are too easy for the oldest examinees. According to Bracken, it is required that test items measure performance at least two standard deviations from the mean for each age range to differentiate the lowest and highest levels of functioning.  PA Composite and APA Composite subtests show insufficient floors for very young children under age 5. For example, a child aged 4 years 0 months who gets a raw score of 1 on each subtest will receive a scaled score of 9 on Elision, and 8 on Blending Words, Sound Matching, and Blending Nonwords subtests.

Conversely, Elision and Phoneme Isolation subtests have insufficient ceilings for older individuals. For example, an individual between 15 years 0 months and 24 years 0 months who answers all items correctly on each subtest will score 13 on the Elision subtest and 15 on the Phoneme Isolation subtest. However, ceiling effects for these subtests may be expected as PA asymptotes develop with age.  

Reliability

CTOPP-2 demonstrates the following reliability evidence:

Internal consistency

Average internal consistency coefficients for:

• subtests exceed the minimal standard of 0.80, except Nonword Repetition, with an average alpha of 0.77

• composites were all 0.85 or higher

Alternate-form reliability

Average alternate-form reliability coefficients for:

• timed subtests met or exceeded 0.85 and

• timed composite scores exceeded 0.90

The CTOPP-2 demonstrated strong reliability coefficients, including alphas and alternate-form reliability, across all sample subgroups,including race/ethnicity, gender, and learning disabilities.

Test–retest

Test–retest correlations for the:

• core subtests ranged from 0.75 to 0.92
• composites ranged from 0.76 to 0.86
• supplemental subtests were 0.73 and 0.75.

Inter-rater reliability

The inter-rater reliability coefficients for a subset of the standardisation sample, assessed by two independent raters associated with Pro-Ed, ranged from 0.96 to 0.98. This high level of agreement indicates that the raters were generally consistent in their evaluations of the CTOPP-2.

Validity

The CTOPP-2 demonstrates strong psychometric evidence supporting its validity:

Concurrent criterion-prediction validity

Across 33 studies involving diverse age groups and reading abilities, the average correlation coefficients for the CTOPP-2 or CTOPP subtests ranged from 0.49 to 0.84, while the composite scores ranged from 0.65 to 0.76, supporting their validity in assessing phonological processing.

Construct-identification validity

A confirmatory factor analysis was performed to examine the relationship of the CTOPP-2 subtests to the key constructs based on a theoretical model of phonological processing that included three distinct but related abilities (phonological awareness, phonological memory, and rapid symbolic naming). The model showed excellent fit for the 7 to 24 year old norming sample, while the 4 to 6 year old model included an additional factor, rapid non-symbolic naming, and also demonstrating a good fit.

Correlation coefficients between CTOPP and CTOPP-2 composite scores and various reading criterion tests were reported, showing average correlation coefficients of 0.48 for phonological awareness, 0.34 for phonological memory, and 0.45 for rapid symbolic naming, indicating moderate relationships between phonological processing and reading skills.

All subtests correlated significantly with age during early development, except for Segmenting Nonwords, which may be more challenging for younger children.

The CTOPP effectively distinguished between normative groups and those with reading or learning difficulties. African American individuals scored slightly below average in phonological awareness but similar in memory and rapid naming, likely due to differences in home language experiences.

Intervention studies showed an average effect size of 0.70 for subtests and 0.60 for composites, indicating the CTOPP-2 as a valuable tool for measuring response to intervention.

Finally, the correlations between individual items within each subtest and the total score of that subtest provide strong evidence of item validity.

Summary

CTOPP-2 is one of the most widely used assessment tools used by speech and language pathologists for evaluating individual’s phonological processing abilities, which are important prerequisites for reading fluency. It is supported by strong reliability and validity data, though floor/ceiling limitations exist at the youngest and oldest ends of its age range. CTOPP-2 plays a major role in speech therapy by identifying early signs of possible reading difficulties and supporting the development of a customised treatment plan to improve the individual’s speech, language, and reading skills.

Resources

Comprehensive Test of Phonological Processing | Second Edition CTOPP-2

Comprehensive Test of Phonological Processing-Second Edition СТОРР-2 Examiner Record Booklet 4 to 6

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