Assessment of student disabilities and factual considerations

Federal legislation requires students with disabilities to participate in state assessments, partly because such assessments are important components of educational accountability. These assessments are used to classify students according to their educational needs, provide information regarding the progress of students with disabilities, and identify the extent to which students are attaining state academic standards. The large majority of classified students are classified under the Individuals with Disabilities Education Act (IDEA). But classification is highly inconsistent, which should raise concerns about over-, under-, and misclassifying certain types of disabilities. Misclassification can result from failing to identify students with disabilities, from classifying students with disabilities they do not have, and from delaying classifying disabilities in students. Some of this inconsistency is accounted for by teachers and schools (McDonnell, McLaughlin, & Morison, 1997); however, when contrasting state classification data there are striking differences that indicate that state guidelines vary and lead to the majority of misclassifications. Nationally 11.6% of students between the ages of 6 and 17 years were served under Part B of IDEA in the 2003-2004 school years (Data Accountability Center, 2009). Part B of IDEA is Assistance for Education of All Children with Disabilities, which is the core section of IDEA that provides most of the state funding. However, this overall classification percentage has demonstrated a highly inconsistent pattern for years and has ranged from 9.1% to nearly 16%. The reported prevalence rates for specific disabilities are very inconsistent from state to state. Based on the categories required for federal reporting, the highest prevalence is for specific learning disabilities making up more than half of the students served under IDEA Part B. However, the percentage of learning disabled students widely varies from 2.39% (Kentucky) to 7.67% (Iowa) across the nation. Discrepancies can be even larger in the case of less common disabilities such as mental retardation with a low of .37% (New Jersey) to a high of 3.06% (West Virginia).

An over-classification of minorities as disabled has been an issue in special education for decades (Harry & Klinger, 2006). The rate of Black and other minority children classified as disabled is much higher than expected given the proportion of minorities to the population. Identifying students as disabled when they are not disabled results in several problems: First, the stigma associated with being labeled and requiring special education can be quite traumatic for students who do not require these services. Such a label can result in lost potential, self-fulfilling prophecies, and emotional problems for students. Second, placing a potentially "normal" student in special education classes can lead to a less rigorous curriculum that can result in poorer secondary and post-educational opportunities. Finally, labeling students as disabled when they are not leads to inappropriate services for mislabeled students and fewer services available for those who need them. Likewise, not identifying students who need special services can lead to distressing effects for a student such as loss of esteem, emotional difficulties, high drop-out rates, high rates of intrapersonal problems, and greater identification with counter-culture alternative life-styles.

Early in the 1990s students with disabilities were often excluded from participating in state and district assessments which resulted in inaccurate views of the success of educational programs, led to increased referrals to special education, allowed for lower expectations for students with disabilities, and resulted in decisions based on inaccurate information. However, the participation in large-scale assessments is now recognized as a crucial part of equal opportunity. Mandating the inclusion of students with disabilities in the general education assessments moved the system into unfamiliar territory. The policy that any statewide assessment is appropriate for the majority of students with disabilities and that only a small percentage will need an alternate assessment results in widely varying rates of identified students and a potential for misclassification. If the populations are misidentified then all other information concerning response to interventions provided for these students is also invalidated. Current models of assessment include the discrepancy models, in which certain standardized test scores must be discrepant to a certain degree in order for a disability to be classified, and the response to intervention models, which can vary from state to state, but essentially state that students who do not show a response to effective interventions are more likely to have biologically-based disabilities and require special education (Jimerson, Burns, & VanDerHeyden, 2007). Both methods have substantial rates of misclassification. To start, there needs to be better descriptive information about the target populations, the contexts in which they are schooled, and the ways in which they are assessed. Any assessment policy cannot be evaluated and as a result any interventions cannot be deemed effective if states cannot identify the target group clearly. The current dramatically inconsistent data on prevalence rates suggest that states are failing to do identify specific disabilities within their systems. There should be a national mandate on how disabilities are assessed, what the criteria for specific disabilities are, what percentages of students of various types are included in the general-education assessments, and what accommodations they are to be provided. This information should be collected in a manner that allows the states to differentiate among types of students, schooling contexts, and types of assessment and accountability systems. There should be greater standardization of definitions and data collection methods. Without such national guidelines, assessing for disabilities in students is much like hunting or fishing, what you find depends on what state you are in.