subtest

Subtest is a discrete component of a larger test or assessment intended to measure a specific domain or skill. In standardized testing and psychological assessment, subtests provide information about particular abilities and contribute to overall scores while preserving detail about individual areas.

In psychology, many major instruments are composed of multiple subtests. For example, intelligence scales may include verbal, perceptual, memory, and processing speed subtests. Each subtest yields a score that is interpreted alongside normative data and, in some cases, combined into composite indexes such as a Full Scale IQ or index scores. Subtest profiles help identify relative strengths and weaknesses and inform clinical or educational decisions.

In educational and achievement testing, subtests target core skill domains such as reading, mathematics, or writing. Subtest results support diagnostic conclusions, progress monitoring, or program placement and can guide instruction without relying solely on a single global score.

In software testing and quality assurance, the term subtest is used informally to describe a smaller test case or scenario nested within a larger test plan. Subtests focus on a particular feature, workflow, or requirement, enabling modular testing, clearer reporting, and easier fault isolation.

Administration and scoring depend on the instrument and domain. Subtest scores are typically standardized using normative samples; their reliability and validity vary by subtest and by age or population. Interpreting subtest results requires consideration of the full battery context and potential ceiling or floor effects.

Subtests are most informative when used to supplement overall scores, providing domain-specific insight rather than a sole measure of ability.