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LinguiSystems Articulation Test (LAT)
Ages: 3-21   Grades: PreK-Adult         

Switch to the LAT and get new norms for 3- to 21-year-olds!  Assess all the consonant sounds and screen for Childhood Apraxia of Speech.

Why should I use the LinguiSystems Articulation Test?

Because you can count on the results and save money too!  The LAT costs 30% less than the GFTA 2.

Test Set
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LinguiSystems Articulation Test FORMS(20)
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Test Purpose
The LAT was designed to identify children and young adults with abnormal articulation patterns.  It ensures a thorough examination of all sounds and blends by presenting several sounds more than one time in the same position.  All positions at the word level are tested.

Test results, in combination with the stimulability and intelligibility ratings and a Childhood Apraxia of Speech Screening included with the LAT, allow the SLP to make appropriate recommendations regarding the type and length of service.  An accurate diagnosis leads to best practice therapy.

The LAT can also be used to measure progress in therapy.


Test Description
The LinguiSystems Articulation Test consists of five picture plates that assess all the consonant sounds in words, including initial blends.  The vocalic /r/ is tested in multiple contexts.

The Stimulability Assessment, administered immediately after an incorrect production is made, determines if the student is able to imitate a correct production.

The Intelligibility Rating Scale is based on the student's type and frequency of errors in a picture description task and helps you determine the type and severity of the speech-sound disorder.

The Articulation Summary is based on the student's type of speech-sound erors at the single-word level.  This allows you to break down the speech-sound errors by substitution, omission, or distortion.

The Apraxia Screening Summary is based on the student's sequential productions of twelve multisyllabic words.  Inconsistent repetition of a multisyllabic word may lead to follow-up tests regarding Childhood Apraxia of Speech (CAS).

The Speech Sound Error Analysis is a two-page summary in the test form that allows you to visually analyze the student's speech errors by word location, type, and stimulability.  All phonemes tested in the LAT are included in the Speech Sound Error Analysis.

The LAT is easy to administer, score, and interpret.


Examiner Qualifications
The test should be administered by a trained professional familiar with speech sound disorders (e.g., speech-language pathologist).


Test Procedures

  • Begin with Plate I, Item 1 regardless of the student's age.  Present each item verbally and administer every item.  Basals and ceilings are not used.  Write the student's response verbatim on the test form.  Allowable prompts are provided for each item.
  • For Stimulability items, test only the sounds in which an error occurred.
  • For Apraxia Screening items, point to each picture and ask the student to say each word three times.

Testing Time

  • 15-20 minutes

Scoring/Types of Scores
A score of 1 or 0 is assigned to each target sound in the stimulus word.  A score of + or - is assigned to sound productions in the stimulability testing.

Total Number of Errors can be converted to:

  • Age Equivalents
  • Percentile Ranks
  • Standard Scores

Discussion of Performance
The Discussion of Performance section found in the Examiner's Manual helps you bridge from assessment to treatment.

Once you've identified the type and severity of your student's disorder, review this section to determine the therapy approach most appropriate for your student.  The Phonological Processing Approaches, Phonological Contrasts Approaches, and Core Vocabulary approach are described in sufficient detail to help you make the determination.

The special populations of Childhood Apraxia of Speech (CAS) and Dysarthria are also addressed in this section.


Standardization and Statistics
The LAT was standardized on 3,030 subjects and an additional 700+ subjects were included in the LAT/GFTA-2 Comparison Study.  These subjects represented the latest National Census for race, gender, age, and educational placement. 

  • Reliability—established by the use of test-retest and internal consistency methods for the total test at all age levels.  The median reliability coefficient is .90 and the SEM is 3.39.  The median item homogeneity coefficient is .91.   Reliability tests include:
    • Test-Retest
    • SEM
    • Item Homogeneity (KR20)
  • Validity—established by the use of content validity which indicated the speech sounds selected were those reflective of phoneme development in children.  Contrasted groups and concurrent validity revealed that the test significantly discriminates between typically-developing subjects and subjects with speech-sound disorders.  All of the correlations are significant at the .01 level.  Validity tests include: 
    • Contrast Groups (t-values)
    • Analysis of Variance (ANOVA)
  • Race/Socioeconomic Group Difference Analysis—conducted at the item and subtest levels.  Tests included Analysis of Variance (ANOVA), Z tests and Chi Square analysis at the subtest level.  Race/socioeconomic level were not found to be strong factors.
  • LAT/GFTA-2 Comparison Study—compared performance for the regular education and articulation disorders groups in twelve age categories (3.0 through 8.11).  Results revealed that the LAT:
    • is better than the GFTA-2 in discriminating between individuals with typical and atypical articulation developmen
    • has better predictive ability than the GFTA-2
    • has a wider range of item difficulty than the GFTA-2
    • scores are generally more accurate than the GFTA-2

Copyright © 2010, 2011

Test Set includes: examiner's manual, picture stimuli book, 20 test forms

I really like the picture scene setup instead of continuously flipping pages!  It allows for more spontaneous speech production and makes it much easier to evaluate intelligibility.

Laura H. Bullard, SLP
Rentz, GA

I like this test because it assesses stimulability and consistency.  I can't wait to use it again.

Bonnie Lee, Ph.D.
Princeton Junction, NJ

I like the LAT a lot because it is quick to administer and has the multisyllabic words to repeat (to screen for childhood apraxia of speech).  I like the storytelling component for assessing overall intelligibility (I used it as an oral language sample too).

Deborah Diedrich-Anderson, SLP
Aurora, CO

I LOVE the LAT!  I was so happy with it that I did an inservice about it for the other SLPs in my department.  The apraxia screening feature is what really drew me to the LAT, but I also like that all the stimulus items are on five pages.  I can also check stimulability right next to the test items instead of waiting until the end of the test.  I use the language sample to assess articulation in spontaneous speech—less scripted than other tests I have used.  I am really so happy to have a testing instrument that I really like.

Suzanne Demparco, SLP
Boston, MA

  • According to ASHA (2008), approximately 24% of the six million students served under IDEA Part B received services for speech or language disorders as their primary disability.
  • An articulation test should include colored drawings with vocabulary targets that are highfrequency items for young children in order to elicit a spontaneous speech sample (Madison, Kolbeck, & Walker, 1982).
  • Standardized articulation and phonology tests allow the speech-language pathologist (SLP) to show the family and teachers how the child is performing on a given skill in comparison to age-matched peers.  Standardized test scores are necessary to secure payment from third-party payers in both the private and public sectors.  Standardized test results provide justification for enrollment in speech services and information on the most appropriate goals to begin intervention (Tyler & Tolbert, 2002).
  • Children diagnosed with childhood apraxia of speech (CAS) often show difficulty with multisyllabic words, showing inconsistent productions across consecutive trials (Forrest, 2003).
  • Intelligibility is a complex measure and the SLP should audio record both the standardized articulation test and a language sample for later phonetic analysis.  The severity of the child's intelligibility, along with stimulability of targeted phonemes, will help the SLP set appropriate therapy goals (Kent, Miolo, & Bloedel, 1994).
  • A recent survey of SLPs found that clinicians typically evaluate children's speech sound disorders using a standardized test, along with assessing overall speech intelligibility, and trial therapy methods, including stimulability of incorrect phonemes (Skahan, Watson, & Lof, 2007).  The LinguiSystems Articulation Test is a standardized articulation test that allows the SLP to test the child's speech-sound system with a variety of age-appropriate words, and provides opportunities for overall intelligibility estimates and stimulability testing.

The LinguiSystems Articulation Test incorporates these principles and is also based on expert professional practice.


American Speech-Language-Hearing Association (ASHA). (2008). Incidence and prevalence of communication disorders and hearing loss in children. Retrieved May 18, 2010, from

Forrest, K. (2003). Diagnostic criteria of developmental apraxia of speech used by clinical speech-language pathologists. American Journal of Speech-Language Pathology, 12, 376-380.

Kent, R.D., Miolo, G., & Bloedel, S. (1994). The intelligibility of children's speech: A review of evaluation procedures. American Journal of Speech-Language Pathology, 3, 81-95.

Madison, C.L., Kolbeck, C.P., & Walker, J.L. (1982). An evaluation of stimuli identification on three articulation tests. Language, Speech, and Hearing Services in Schools, 13(2), 110-115.

Skahan, S.M., Watson, M., & Lof, G.L. (2007). Speech-language pathologists' assessment practices for children with suspected speech sound disorders: Results of a national survey. American Journal of Speech-Language Pathology, 16, 246-259.

Tyler, A.A., & Tolbert, L.C. (2002). Speech-language assessment in the clinical setting. American Journal of Speech-Language Pathology, 11, 215-220.


Linda Bowers, Rosemary Huisingh


Linda Bowers, M.A., SLP, is a co-founder and co-owner of LinguiSystems.  She is a speech-language pathologist with wide experience serving language-disordered students of all ages.  Linda has keen professional interest in the thinking, listening, and language abilities of children and adults.

Rosemary Huisingh, M.A., SLP, is also a co-founder and co-owner of LinguiSystems.  As a speech-language pathologist, she has successfully served the communication needs of school children for many years.  Rosemary is particularly interested in childhood language, vocabulary, and thinking skills.