A child struggles in the classroom. The school evaluates. A single standardized test comes back with a score, and that score becomes the answer: eligible or not eligible, disorder or no disorder.

For a monolingual English-speaking child, that approach is already too thin. For a multilingual child, that test score can be misleading. A single score can't tell that story on its own.

This is where the idea of converging evidence comes in. This idea is important whether you're a parent trying to make sense of an evaluation, an advocate reviewing a file, or an attorney building a case.

What Federal Law Requires

IDEA's regulations require using more than one source of information. Under 34 C.F.R. § 300.304(b), a public agency conducting an evaluation must:

• Use a variety of assessment tools and strategies to gather relevant information about the child, and

• Not use any single measure or assessment as the sole criterion for determining eligibility or planning the child's program.

A single test score, however official-looking and precisely calculated, is never supposed to be the whole basis for a life-shaping decision. The same section also requires that assessments be selected and administered without racial or cultural discrimination and, where appropriate, in the child's native language. These requirements are enormously important for Culturally and Linguistically Diverse learners specifically.

What the Research Says

The research backs this up directly for multilingual learners. A widely cited 2020 study by Castilla-Earls and her colleagues recommends a converging evidence approach to determining eligibility for multilingual learners, built on four sources of information: 

• Language experience questionnaires 

• Language and speech samples 

• Standardized testing

• Measures of learning potential, such as dynamic assessment

No one source is treated as sufficient on its own. The point of the framework is that these sources are meant to be weighed together, and a decision that leans on only one of them is missing the rest of the picture the research says is necessary.

What It Looks Like When Convergence Is Missing

When an eligibility decision rests on a single source of data, it risks misidentification.

A multilingual child's typical language development can be mistaken for a disorder because a test was not built for their language history. That child can end up placed in services they don't need, and carrying an eligibility category that follows them for years.

It can also run the other way: a language disorder gets waved away as "still learning English" or normal multilingual variation, and the child who needs support doesn't get it, sometimes for years.

Either outcome is a life-altering decision built on thin data.

What to Look For

If you're reviewing an evaluation file, a few questions can tell you quickly whether convergence was actually happening:

• Was more than one type of data used? Observation, history, and language sample data too?

• Did parents and teachers have input into the picture in both of the child's languages where relevant?

• Were both of the child's languages considered, or was the evaluation conducted only in one? If so, why?

• Where different sources of information point in different directions, does the file explain why and what it means?

A no to any of these doesn't automatically mean the evaluation was wrong. It does mean the evaluation may need a closer look.

If you're a parent, advocate, or attorney trying to determine whether an evaluation gives you the full picture, that's exactly the kind of question my practice exists to help answer. Schedule a complimentary consult here.

References

Castilla-Earls, A., Bedore, L., Rojas, R., Fabiano-Smith, L., Pruitt-Lord, S., Restrepo, M. A., & Peña, E. (2020). Beyond Scores: Using Converging Evidence to Determine Speech and Language Services Eligibility for Dual Language Learners. American Journal of Speech-Language Pathology, 29(3), 1116–1132. https://doi.org/10.1044/2020_AJSLP-19-00179

U.S. Department of Education. (n.d.). Sec. 300.304 Evaluation procedures. Individuals with Disabilities Education Act. https://sites.ed.gov/idea/regs/b/d/300.304/b