Developer Q&A: Dr. Nickola Nelson on The TILLS Advantage

A key difference is that TILLS is validated for identifying disorders of both language and literacy. We refer to this as "language/literacy disorder" to communicate that language IS literacy and literacy IS language. TILLS is unique because it can show how a student’s oral and written language skills relate to each other at the sound/word structure level and at the sentence/discourse level. This information can be used in determining eligibility for special education services based on the presence of language impairment and/or learning disability.

Some other language tests have supplemental reading and writing tasks, but they are not designed to show profiles of interrelated oral and written language difficulties. To be more specific, some language assessments have reading comprehension and structured writing subtests, but they are not included in the core scores or index scores. Others yield reading and writing scores, but they use a scatter shot approach to measure a mixture of skills, which may be scored with single rubrics. That makes it difficult to interpret abilities on written language tasks relative to the student’s performance on comparable oral language tasks.

In contrast, using TILLS allows examiners to compare performance on Nonword Reading and Nonword Spelling with performance on oral tasks involving Nonword Repetition and Phonemic Awareness. This can help teams decide whether knowledge of phonological and morphological word structure is a strength or weakness that should be considered as part of intervention planning. Likewise, examiners can compare Listening Comprehension and Reading Comprehension directly to decide whether sentence/discourse problems are present, or, if Reading Comprehension is lower than Listening Comprehension, whether Reading Comprehension may be hampered by reading decoding problems.