What is the PLS-5? The Preschool Language Scales explained

The PLS-5 (Preschool Language Scales, Fifth Edition) is a standardized language assessment published by Pearson in 2011 for children from birth through age 7 years, 11 months. It measures two broad areas, "Auditory Comprehension" (how well a child understands language) and "Expressive Communication" (how well a child uses sounds, gestures, and words to communicate), which combine into a Total Language score reported on the familiar mean-100 scale. Speech-language pathologists use the PLS-5 to identify language delays in infants, toddlers, and preschoolers, and it is one of the most widely used instruments for documenting eligibility for early intervention services. This article explains what the test covers, how a language test for a baby actually works, how the scores are interpreted, and how the PLS-5 relates to assessments for older children and adults.

According to Pearson, the PLS-5 was developed by Irla Lee Zimmerman, Violette G. Steiner, and Roberta Evatt Pond, and it evaluates language across two core scales plus a composite.

• Auditory Comprehension: the receptive side of language. For infants this includes attention to voices and responses to sound; for preschoolers it moves into understanding vocabulary, concepts, grammar, and following directions.

• Expressive Communication: the productive side. Early items sample babbling, gestures, and social communication, while later items cover naming, sentence structure, and using language to reason and tell simple stories.

• Total Language score: the combination of the two scales, which serves as the overall summary of the child's language development.

Reach Out and Read, a pediatric literacy nonprofit that catalogs child development measures, describes the PLS as assessing skills "that range from preverbal, interaction-based, to emerging language, to early literacy," touching attention, play, gesture, vocal development, social communication, semantics, and language structure. In other words, the test is built to follow language from its earliest roots in eye contact and turn-taking all the way to the doorstep of reading.

The PLS-5 covers birth through 7:11, an unusually wide span that starts earlier than almost any other standardized language measure. Pearson reports a typical administration time of 45 to 60 minutes, with the child responding by pointing, playing with objects, or answering verbally depending on age. Test kits include picture books and manipulatives, and the youngest items are scored largely from what the examiner observes during structured interaction.

Because very young children do not always perform on cue, the PLS-5 includes a "Home Communication Questionnaire," a caregiver-report form used for children from birth through age 2. Parents answer questions about the communication behaviors they see at home, which gives the examiner evidence about skills a baby may not display in an unfamiliar clinic room. Pearson also packages a brief articulation screener with the kit, so the examiner can check speech-sound production in a couple of minutes without a separate test.

The examiner is normally a speech-language pathologist. The American Speech-Language-Hearing Association notes that assessment of early language relies on multiple sources of information, including parent and caregiver report, developmental observation, and language sampling alongside standardized measures. The PLS-5 is designed to slot into exactly that kind of multi-source evaluation rather than stand alone.

The PLS-5 reports "standard scores" with a mean of 100 and a standard deviation of 15, the same metric used by most IQ and achievement tests. A score near 100 is typical for the child's age, and the standard deviation (a measure of how spread out scores are) means that roughly two thirds of children score between 85 and 115. Pearson reports standard scores and percentile ranks for Auditory Comprehension, Expressive Communication, and Total Language, along with growth scores for tracking progress over time and language age equivalents.

The norm sample was built to match updated U.S. Census figures for region, race and ethnicity, and caregiver education, according to the publisher. On accuracy, Reach Out and Read reports a sensitivity of .83 and a specificity of .80 for the Total Language score in detecting language delay. Those figures mean the test catches most true delays but is not infallible in either direction, so a single below-average score is a signal to investigate further rather than a verdict.

Two cautions apply. Age-equivalent scores ("your child communicates like an 18-month-old") are intuitive but statistically crude, and most clinicians treat standard scores and percentiles as the primary results. And like any test score, a PLS-5 result carries measurement error; scores describe performance on one day, in one setting, with one examiner.

Parents are often puzzled by the idea of giving a standardized test to a 9-month-old. The answer is that infant assessment is built on structured observation rather than questions and answers. The examiner presents specific situations (a rattle, a game of peekaboo, a picture book) and records whether the child shows the expected behaviors: turning toward a voice, following a point, imitating sounds, using gestures to request. Each behavior has a known typical age of emergence, so the pattern of what a baby does and does not do can be scored against national norms.

Caregiver report fills the gaps. A baby who says several words at home may say none in a clinic, which is why the Home Communication Questionnaire and the parent interview carry real weight in scoring the earliest items. ASHA's guidance stresses observing children in play with familiar people for the same reason. The interaction-based design also means results for infants and toddlers are best treated as a snapshot of a fast-moving target; language in the first three years develops in bursts, and early intervention programs typically re-evaluate rather than rely on one administration.

Pearson publishes a separate PLS-5 Spanish edition (2012) covering the same birth to 7:11 range. Rather than simply translating the English items, it was normed on 1,150 monolingual and bilingual Spanish-speaking children in the United States and Puerto Rico, and it offers "bilingual-conceptual" scoring, meaning the child's abilities in both Spanish and English are captured in one score. That matters because a bilingual toddler may know "leche" but not "milk," and testing in only one language can make a typically developing child look delayed. Dual-language administration takes roughly 20 to 65 minutes, per the publisher. The test has also been adapted internationally; a 2017 study in the International Journal of Pediatric Otorhinolaryngology reported a valid and reliable Turkish adaptation, the TPLS-5.

The PLS-5 sits at the beginning of a testing pipeline that continues into school age and beyond. When a child outgrows it, clinicians typically move to the CELF-5 (Clinical Evaluation of Language Fundamentals, Fifth Edition), Pearson's language battery for ages 5:0 through 21:11; the two tests deliberately overlap between ages 5 and 7. You can read our full guide to the CELF-5 for details. For a quick, vocabulary-focused measure, examiners often add the Peabody Picture Vocabulary Test, which children answer just by pointing.

It is worth being clear that the PLS-5 is a language test rather than an IQ test. Language ability correlates with general cognitive ability, and verbal reasoning is a major component of most intelligence tests, but a low PLS-5 score indicates a need for language support; on its own it says little about a child's intelligence. A child with a speech delay can have entirely typical nonverbal reasoning.

For adults curious about their own cognitive profile, the equivalent of a well-normed instrument is the RIOT IQ test (the Reasoning and Intelligence Online Test), developed by RIOT IQ with psychometrician Dr. Russell T. Warne for adults 18 and older. It includes 15 subtests across six cognitive indices (verbal reasoning, fluid reasoning, spatial ability, working memory, processing speed, and reaction time), takes about 52 minutes, and reports scores on the same mean-100, SD-15 scale the PLS-5 uses. Like any online measure, it does not replace an individually administered diagnostic evaluation, but it applies the same psychometric standards described above. You can take it at riotiq.com.

Birth through 7 years, 11 months, according to Pearson. It is one of the few standardized language tests with norms that start at birth.

No. It measures receptive and expressive language rather than general intelligence. It uses the same mean-100, SD-15 score scale as IQ tests, which sometimes causes confusion.

Pearson lists 45 to 60 minutes for the English edition. Time varies with the child's age and attention, and the caregiver questionnaire can be completed separately.

Practices vary, but scores more than 1 to 1.5 standard deviations below the mean (below about 85 to 78) are commonly used as cutoffs for early intervention eligibility, depending on state and program rules.

Yes. The PLS-5 Spanish (2012) was normed on 1,150 Spanish-speaking children in the U.S. and Puerto Rico and uses bilingual-conceptual scoring that credits skills in either language.

The PLS-5 covers birth to 7:11 and leans on play, objects, and caregiver report; the CELF-5 covers ages 5 to 21 and uses more formal, school-style language tasks. Clinicians choose between them for 5- to 7-year-olds based on the child's level.

1. Pearson. (2011). Preschool Language Scales, Fifth Edition (PLS-5). Pearson Assessments. pearsonassessments.com

2. Pearson. (2012). Preschool Language Scales, Fifth Edition Spanish (PLS-5 Spanish). Pearson Assessments. pearsonassessments.com

3. Pearson. (2013). Clinical Evaluation of Language Fundamentals, Fifth Edition (CELF-5). Pearson Assessments. pearsonassessments.com

4. Reach Out and Read. (n.d.). Preschool Language Scale (PLS). reachoutandread.org

5. American Speech-Language-Hearing Association. (n.d.). Late language emergence (Practice Portal). asha.org

6. Sahli, A. S., & Belgin, E. (2017). Adaptation, validity, and reliability of the Preschool Language Scale-Fifth Edition (PLS-5) in the Turkish context: The Turkish Preschool Language Scale-5 (TPLS-5). International Journal of Pediatric Otorhinolaryngology, 98, 143-149. doi.org

7. ConductScience. (n.d.). PLS-5 (Preschool Language Scales, Fifth Edition): Subtests and uses. conductscience.com

Hero photo: A plush bunny and monkey share an open baby picture book at a child-sized library table. Photo by Baltimore County Public Library, CC BY 2.0, via Wikimedia Commons.