Diagnostic Tests

Diagnostic tests in education are measurement methods that aim at identifying specific aspects in the field of teaching and learning. In psychology and medicine, the term diagnostic refers to making a medical diagnosis of a disease. The term also sometimes refers to any test that produces a profile of scores with strengths and weaknesses. This entry does not discuss the term in those contexts. Testing in this context means assessing one or more clearly defined criteria such as school achievement, student motivation, or learning disabilities. In a scientific understanding, tests need to be constructed using specific methods, need to meet specific quality criteria, and need to be conducted under specific rules. Teachers and educators need to evaluate and analyze diagnostic test results in order to use them for their teaching and instructional program. Results of diagnostic tests illustrate the extent to which the measured aspect exists and can be used to optimize teaching and learning in educational contexts.

Diagnostic tests are a major part of and great possibility for assessing relevant aspects of teaching and learning in educational systems. In order to optimize teaching, the assessment of learning-relevant aspects is indispensable. In this regard, [Page 513]and with reference to high-stakes testing, educational measurement, and evaluation, diagnostic tests have great influence on and strongly result in the changes of educational systems and instructional programs.

This entry initially describes functions and forms of diagnostic tests in educational purposes. More precisely, diagnostic subjects as well as different possibilities to assess the relevant data are presented. Subsequently, special characteristics of diagnostic tests are described that enable a classification of different test formats. This includes the description of the classical quality criteria for tests, the comparison of formal/standardized and informal tests, tests at an individual or group level, norm-referenced and criterion-referenced tests, as well as summative and formative tests. These classification aspects lead to describing possible uses of diagnostic tests in the school context as well as competence that are required by teachers and educators who conduct these diagnostic tests—the so-called diagnostic competence. An overview of three diagnostic tests exemplifies the described functions and classifies the relevant test characteristics.