The Battelle Developmental Inventory, Third Edition (BDI-3) is an individually administered assessment that measures how well a child from birth through age 7 years, 11 months is mastering developmental milestones in five domains: adaptive, cognitive, communication, motor, and social-emotional. Authored by Jean Newborg and published by Riverside Insights in 2020, it is one of the most widely used tools in the United States for deciding whether young children qualify for early-intervention or preschool special education services. The BDI-3 measures developmental progress rather than intelligence, so it is a milestone inventory and it is not an IQ test. This article explains what the BDI-3 covers, how examiners administer it, what its scores mean, and where its limits lie.
What the BDI-3 measures
According to Riverside Insights, children typically attain critical skills and behaviors in a sequence that runs from simple to complex, and the BDI-3 measures a child's mastery of those milestones in five "global domains," each built from smaller subdomains. In total the test contains 13 subdomains, and the publisher's technical bulletin notes that all 13 are administered to children ages 6 and older, with younger children taking only the age-appropriate subset.
• Adaptive: everyday independence, measured through the self-care subdomain (skills such as eating, dressing, toileting, and sleeping) and a personal responsibility subdomain.
• Social-emotional: interactions with adults, interactions with peers, and the child's self-concept and social role. The publisher notes this domain was named "personal-social" in the second edition and was reorganized to reflect current social-emotional research.
• Communication: "receptive" language (what the child understands) and "expressive" language (what the child can say), with expanded coverage of speech articulation in this edition.
• Motor: gross motor skills such as climbing stairs, fine motor skills such as manipulating small objects, and perceptual motor skills such as copying shapes and letters.
• Cognitive: attention and memory, perception and concepts, and reasoning and academic skills.
Beyond the five domains, the BDI-3 added the Battelle Early Academic Survey, a battery that measures foundational literacy and mathematics skills in children ages 3 years, 6 months to 7 years, 11 months. Riverside reports it can be given alone or alongside the rest of the test and takes under 30 minutes.
How the BDI-3 is administered
The BDI-3 is given one-on-one by a trained examiner, and its signature feature is flexibility in how each item is credited. The publisher's brochure describes three administration formats.
• Structured: play-based activities using child-friendly manipulatives, such as retrieving a toy, sorting shapes, or pointing to pictures the examiner names.
• Observation: the examiner watches the behavior occur in the child's natural setting, for example noting whether a child puts on shoes independently during a preschool routine.
• Interview: scripted questions for a parent or caregiver, used when a behavior is hard to elicit on demand or happens mainly at home.
An examiner can begin with any domain and administer one domain, several, or the full battery depending on the referral question. Items follow "basal" and "ceiling" rules: per Riverside's administration guidance, a basal is established when the child earns full credit on three consecutive lowest-numbered items, and testing in a subdomain stops when the child scores zero on three consecutive highest-numbered items. The publisher does not publish a single fixed time for the complete battery because length depends on how many domains the team administers. Administration and scoring run through the web-based Riverside Score system, with a companion mobile app for iOS, Android, and Windows that works offline. A Spanish edition is available and was normed on a separate sample of 1,000 bilingual children.
The screener and the full battery
Programs that need to check large numbers of children quickly use the BDI-3 Screening Test, a subset of items drawn from each of the five domains. Riverside lists an administration time of 10 to 30 minutes and provides cut scores at 1.0, 1.5, and 2.0 "standard deviations" (a measure of how far a score falls from the average) below the mean. A child who falls below the chosen cut point is referred for the full BDI-3 developmental battery, which yields the detailed domain scores that eligibility decisions require. This two-step logic mirrors other early-childhood tools such as the Denver-II developmental screening test, which likewise flags children for fuller evaluation instead of diagnosing anything by itself.
How BDI-3 scores work
The full battery produces a "developmental quotient" for each domain plus a Total Developmental Quotient across all five. These are standard scores with a mean of 100 and a standard deviation of 15, the same metric IQ tests use, which is one reason people confuse the two kinds of instruments. Each subdomain yields a "scaled score" with a mean of 10 and a standard deviation of 3. Riverside's standardization flyer also lists percentile ranks, age equivalents, growth-oriented Change Sensitive Scores, and three delay metrics (months of delay, percentage of delay, and standard deviation of delay) that map directly onto the cutoff rules many states write into their early-intervention eligibility criteria.
The norms come from a standardization sample of 2,500 children, about 125 in each of 20 age groups, tested by 283 examiners across 44 states, and the publisher reports the sample reflects U.S. census estimates and 2020 population projections. Reliability evidence in the brochure shows internal consistency coefficients of .92 to .97 across the five domains, with test-retest values from .79 to .87. Those figures are strong for an early-childhood measure, though the lower stability estimates are a reminder that very young children's scores can shift between sessions, so teams should treat any single administration with appropriate caution.
The BDI-3 in early intervention and special education
The Battelle's biggest footprint is in services under the Individuals with Disabilities Education Act. Riverside states that the BDI-3 is aligned with IDEA Part C, which covers infants and toddlers from birth to age 3 through Individualized Family Service Plans, and Part B Section 619, which covers preschoolers ages 3 to 5 through Individualized Education Programs, and that it meets federal reporting requirements for Part C, Part B/619, and Head Start programs. State guidance shows how this works in practice: South Dakota's Department of Education, for example, directs evaluation teams to the BDI-3 for developmental delay eligibility in ages 3 to 5 and requires it for progress monitoring on the state's preschool outcomes indicator, with exit testing completed within 90 days of a child's sixth birthday.
Federal reporting is the second major use. The Office of Special Education Programs requires every state to report the percentage of children in Part C and Part B 619 programs who improve on three child outcomes: positive social-emotional skills, acquisition and use of knowledge and skills, and use of appropriate behaviors to meet needs. The Early Childhood Technical Assistance Center publishes a crosswalk that maps each BDI-3 domain and item onto those outcomes, which lets states convert Battelle scores directly into the numbers they submit to the federal government.
No single test decides eligibility on its own. Teams combine the BDI-3 with other sources, and depending on the concern they may add adaptive behavior measures such as the Vineland-3 or, for infants and toddlers, individually administered developmental scales such as the Bayley-4.
Is the Battelle an IQ test?
No. The BDI-3 reports scores on the familiar mean-100 scale, but it measures whether a child has reached milestones that most children attain by a given age, which is a different question from the reasoning-under-novelty question an intelligence test asks. State guidance is blunt on this point: South Dakota's eligibility Q&A describes the BDI-3 cognitive domain as more academic than intellectual and states that the BDI-3 is not a comprehensive evaluation of ability, directing teams toward dedicated ability measures when an intellectual disability is suspected. The Battelle's strengths are its flexible multi-source administration, its alignment with federal reporting, and norms built specifically for very young children. Its limits are just as clear: it stops at age 7 years, 11 months, its scores run slightly higher than the previous edition's, and a developmental quotient says little about long-term cognitive ability.
For older examinees the toolbox changes. Adults who want a normed measure of cognitive ability can take the RIOT IQ test, the Reasoning and Intelligence Online Test developed by RIOT IQ with psychometrician Dr. Russell T. Warne. It is designed for adults 18 and older, uses 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, standard-deviation-15 scale. Like any online measure, it complements rather than replaces an individually administered diagnostic evaluation.
Frequently asked questions
What ages does the BDI-3 cover?
The BDI-3 is normed for children from birth through age 7 years, 11 months. The Battelle Early Academic Survey component covers ages 3 years, 6 months through 7 years, 11 months.
Is the Battelle Developmental Inventory an IQ test?
No. It measures mastery of developmental milestones in adaptive, social-emotional, communication, motor, and cognitive domains. Even its cognitive domain reflects early skills and concepts rather than the broad reasoning ability an intelligence test measures.
How long does the BDI-3 take?
The BDI-3 Screening Test takes about 10 to 30 minutes. The full battery has no single published time because examiners can administer one domain, several, or all five depending on the evaluation question.
What do BDI-3 scores mean?
Domain scores and the Total Developmental Quotient use a mean of 100 and a standard deviation of 15, and subdomain scaled scores use a mean of 10 and a standard deviation of 3. Scores well below 100, often 1.5 to 2 standard deviations below, can support eligibility for early-intervention or preschool special education services depending on state rules.
Who administers the BDI-3?
Trained examiners such as early-intervention specialists, early-childhood special educators, school psychologists, and related service providers give the test one-on-one, using structured play tasks, observation, and caregiver interviews.
Why do early-intervention programs use the Battelle so widely?
Its five domains match the developmental areas IDEA requires teams to evaluate, and its scores map onto the three child outcomes that states must report to the U.S. Department of Education, so one instrument can serve both eligibility and federal reporting.
3. Riverside Insights. (n.d.). BDI-3: Development at-a-glance. Standardization/norms.. info.riversideinsights.com
4. Custer, M., Ledbetter, M., & Snader, E. (2020). Score differences between the BDI-3 and BDI-2 NU standardization samples (BDI-3 Assessment Service Bulletin No. 1). Riverside Assessments. pages.nelson.com
5. Early Childhood Technical Assistance Center. (2026). The Battelle Developmental Inventory, Third Edition (BDI-3) crosswalk to the three child outcomes.. ectacenter.org
6. Early Childhood Technical Assistance Center. (n.d.). Child outcomes.. ectacenter.org
7. South Dakota Department of Education. (2025). Ages 3-5 eligibility, developmental delay and progress monitoring Q&A.. doe.sd.gov
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