Bias occurs when one interprets or judges others based on their own background and experience. This results in viewing other practices, expectations and perceptions as inferior or wrong and can result in many different consequences. 

The biggest consequence of bias in speech and language assessment is misdiagnosis. This can mean the overidentification of typically developing students from culturally or linguistically diverse backgrounds. The language from IDEA 2004 recognized this problem: “More minority children continue to be served in special education than would be expected from the percentage of minority students in the general population” [20 U.S.C § 1400 (c)(12)(B)]. This indicates that large numbers of children from diverse backgrounds are being mislabeled as having a speech and language disability when they do not.

What’s wrong with identifying a child with a disability when the child does not have one? It affects the student’s as well as others’ impression of the intelligence and academic potential of the child, which can lead to decreased academic and post-secondary opportunities (Harry & Klingner, 2006). Special education services often mean reduced academic rigor and expectations (Harry & Klingner, 2006). Students in special education also have less access to academically able peers (National Research Council, 2002) who could serve as models for those students struggling academically. It can also mean that children from backgrounds who normally do better may not be identified as having an impairment because the bias is in their favor. These children may struggle academically without the support they truly need because they are not identified by norm-referenced tests.

Bias can occur throughout the assessment process both in the evaluator as well as in testing materials. Bias in the evaluator happens when the evaluator measures the children being assessed against his or her own perceptions and expectations of child development. A child should always only be compared to his or her speech community. ASHA (American Speech-Language-Hearing Association) states that a Speech Language Pathologist should establish “appropriate criteria for distinguishing a disorder from a difference by using the norms of the client’s/patient’s speech community as the standard.”

Bias is evident within assessment materials, especially norm-referenced, criterion referenced and standardized tests. In norm-referenced tests, bias is often present in test items and the normative sample. Test items may reflect the perceptions and expectations of the test designers, such as the assumption that certain vocabulary items have been acquired by a certain age (e.g., colors, shapes). It is also noticeable in the norms which have been developed based on children from different cultural, linguistic and socioeconomic status backgrounds. Even though culturally and/or linguistically diverse children may be included in the normative sample, they are not present in numbers sufficient to be representative of the speech community of most culturally and/or linguistically diverse children.


Test Scores and Disproportionate Referrals 

Socioeconomic, Linguistic and Cultural Bias in Testing and Labeling Tasks

Clinical Judgment/ Informed Clinical Opinion Part 1

Clinical Judgment/ Informed Clinical Opinion Part 2


Harry, B. & Klingner, J., (2006). Why are so many minority students in special education?: Understanding race and disability in schools. New York: Teachers College Press, Columbia University.

Individuals with Disabilities Education Improvement Act of 2004, H.R.1350,108th Congress (2004)

National Research Council. (2002). Minority students in special and gifted education. Committee on Minority Representation in Special Education, M. Suzanne Donovan and Christopher T. Cross (Eds.). Division of Behavioral and Social Sciences and Education. Washington, DC: National Academy Press.