Interim, Formative, and Diagnostic Assessments

Interim assessments, formative assessment processes, diagnostic assessments, and other non-summative assessments (e.g., classroom-based assessments) are key parts of a comprehensive assessment system. These assessments provide information that educators use to guide instruction. Universal design principles can maximize the accessibility of these assessments.

The definitions of the terms for these assessments vary, often resulting in confusion. General definitions include:

Interim assessments refer to assessments that are administered several times during a school year to measure student progress. Most often, these are commercially produced. Other terms that are sometimes used to describe these assessments are local assessments and “formative assessments.” Data from interim assessments are used for a variety of purposes, including: measuring growth or progress, instructional decision making, and predicting summative assessment performance. There is also interest in using these assessments to measure learning loss.

The Individuals with Disabilities Education Act (IDEA) requires students with disabilities be included in all general state and districtwide assessment programs, including districtwide administrations of interim assessments, with appropriate accommodations and alternate assessments.

Formative assessment refers to processes used by teachers and students during instruction to obtain feedback that is used to adjust instruction to improve student learning. Formative assessment is very useful when instructing students with disabilities, English learners, and English learners with disabilities. The formative learning cycle is based on students having an awareness of what they are trying to learn and what it will look like when they do (Where am I going?). In the formative learning cycle, feedback becomes information students need and want (Where am I now? Where to next?).

Diagnostic assessments provide data about students' knowledge and skills before instruction. These data can be used for placement as well as for instructional planning and decision making, depending on their focus. Interim assessments and formative assessment processes would be considered diagnostic assessments when they are administered as a pre-assessment used for instructional decision-making.