Top 7 Benefits of TILLS

January 28, 2025

If you’re an SLP, special educator, or reading specialist, you might already use the Test of Integrated Language & Literacy Skills™ (TILLS™) or you might just be curious about this groundbreaking test that’s used across the country.

Developed by a team of highly respected experts (Nickola Nelson, Elena Plante, Nancy Helm-Estabrooks, and Gillian Hotz) TILLS tests oral and written language skills in students ages 6–18 years. It’s used to identify and diagnose language and literacy disorders (including dyslexia and developmental language disorder), document patterns of relative strengths and weaknesses, and track changes in language and literacy skills over time.

Here are some features and factors that set TILLS apart from other assessments:

• More comprehensive assessment. TILLS is the only test that assesses both oral AND written language with an evidence-based model that shows how these skills relate to each other. TILLS incorporates two effective models: the Language Levels x Modalities Model and the Quadrant Model. These models work together to uncover the nature of a student’s strengths and weaknesses across both oral and written modalities. See the models here.
• More sensitive to picking up disorders. The TILLS normative sample only includes typically developing students, in order to provide the most accurate assessment and to support the major purpose of the test—to identify the presence of language/literacy disorders. Including only students without impairment in the normative group establishes a standard for typical performance that can be differentiated from the performance of students with language and literacy disorders.
• More meaningful results. TILLS uses percentile ranks, not Normal Curve Equivalent (NCE) percentiles, to give additional rich information about the number of students in the norm reference group who earned a raw score lower than your student. NCE percentiles give the same information as standard scores and assume the normative distribution is a perfect bell curve. TILLS percentile ranks reflect the actual curve of the underlying normative distribution, thus providing more information to inform diagnostic decisions.
• Recognizes the influence of low socioeconomic status (SES). Evidence-based adjustments to cut scores were determined to prevent over-identification of students when influences of low SES may be a primary concern, rather than language impairment.
• One test is best. With TILLS, you get the full picture of oral and written language skills with just one test kit. Because you’re not administering items from multiple tests, you can compare results in different areas and know that your results are psychometrically sound.
• Powerful TILLS profile. TILLS profiles give you an at-a-glance understanding of your students’ strengths and needs—something other tests can’t offer. These profiles help you communicate with others, pinpoint what to work on, diagnose and recognize profiles of disorders, and easily track changes in specific areas of concern. Read these case stories for examples.
• A real time-saver. If you’re an experienced clinician, you can administer TILLS in 90 minutes or less. (It can also be chunked into several sessions.) You’ll spend less time testing and more time helping students. The time you do spend testing will be meaningful and relevant to understanding your students’ needs.

Want to learn more about TILLS? Visit the TILLS website for an introductory webinar, FAQs, a 28-page sampler, case stories, an extended FAQ, and much more.