A Black student at a school with few other Black children is more likely to be diagnosed with a learning disability than a similarly performing child at a predominantly Black school, a new study in Society and Mental Health found. It’s a similar case with kids still learning the English language.

According to the study, even when children had the same test scores and social backgrounds, one could be determined to have a learning disability in one school, and not in another. The findings reveal not only that learning disability classifications in the U.S. are subjective and inconsistent, but that they are prone to bias based on context.

Every year, around 6 million students with disabilities get support through the Individuals with Disabilities and Education Act (IDEA). On paper, racial minority children are overrepresented in special education. According to nationwide data, there are more Black, Hispanic, and Native American children than white children in programs for learning and intellectual disabilities, like dyslexia, as well as conditions like ADHD and autism.

In 2007, eight experts in psychology, policy, education, and civil rights even went before The United States Commission on Civil Rights in Washington D.C. to express concern that these students were being misplaced due to racial biases and lower academic expectations. In 2016, in response to this issue, IDEA implemented new regulations that required states to identify districts with "significant disproportionality" in students being directed to special education.

But the new research shows that there are other social and contextual factors playing a strong role in determining disability. Dara Shifrer, the new study’s first author and an assistant professor at Portland State University, said that we should be wary of this issue, since the word “disability” often implies biological and neurological differences. Disability diagnosis can impact the trajectory of a child's education, by changing the types of classes they take, teachers they have, and material they're provided and exposing them to possible stigma.

Shifrer and the team looked at data from 378,919 kids in an urban school district between 2006 and 2012. They found that Black children that go to schools with a lower proportion of other Black students to other races are more likely to be diagnosed as disabled.

The same was true about kids who were learning English as a second language—the fewer other English-learners there were, the more likely they would end up in special education programs. Being a low-achiever in a high-achieving school also meant a child was more likely to be diagnosed as disabled compared to if they were performing at the same level, but in a generally low-achieving school.

Shifrer was a middle school math teacher before she started studying how to predict who gets a disability classification. “The dominant narrative for decades emphasized the over-representation of racial minorities,” she said. But in the past 10 years, the debate on overrepresentation of minorities in special education has become more nuanced.

When researchers controlled for social influences, like poverty, and compared students that were mostly the same except for the color of their skin, it was actually the white children that were more likely to be in special education programs.

George Farkas, a professor of education and sociology at The University of California Irvine and co-author of many studies that has replicated this finding, said that the overwhelming belief in overrepresentation might have actually "denied needed services to Black and latinx students." Since then, there's been a kind of academic tussle: Are racial minority children over or underrepresented?

Shifrer said it comes down to how you crunch the numbers. Learning disabilities are often designated in schools based on low academic performance, or low achievement despite a high IQ. Statistical techniques that group kids that are similar achievers, and control for all other factors, find that racial minorities are slightly less likely than whites to be given a disability diagnosis.

But since racial minorities, overall, make up a larger share of the low-achiever pool, in raw numbers, they are still more likely than white children to end up in special education. “Real life is not statistically adjusted," Shifrer said.

Environmental, economic, and social factors can influence achievement levels too, and data show that minority kids are more likely to be dealing with many of these factors. Black children are more likely to live in poor families, have food insecurity, and be exposed to toxic environments like lead or hazardous waste.

The representation debate could be missing the bigger picture: how social inequality and racism outside of school can make its way into classrooms and interfere with learning. The higher rates of special education might not be due to an overwhelming racial bias from teachers, but from racial inequalities built into daily life that lead to lower achievement, said Rachel Fish, an assistant professor at NYU in the Department of Teaching & Learning and co-author on the new study.

In their research, Fish said they compared students who had similar achievement levels, which implies that disability diagnoses were made not on academic grounds— but on qualities that have nothing to do with neurological differences.

“This suggests that disability classifications occur subjectively and inconsistently, which runs counter to how we perceive and act on disability labels,” Shifrer said, which is that they connote a biological difference.

While it’s crucial for students who need special education to have access to it, Shifrer and Fish said their study is a reminder that since there are no definitive biomarkers for cognitive disorders and mental illnesses, our ways of determining who has them are foggy and clouded by social influences.