The 'obsolescence' of assessment procedures.

The concept that obsolescence or being "out of date" makes a test or procedure invalid ("inaccurate," "inappropriate," "not useful," "creating wrong interpretations," etc.) has been widely accepted in psychology and neuropsychology. Such obsolescence, produced by publishing a new version of a test, has produced an extensive nullification of research effort (probably 10,000 Wechsler studies). The arguments, attempting to justify obsolescence, include the Flynn Effect, the creation of a new version of a test or simply time. However, the Flynn Effect appears to have plateaued. In psychometric theory, validated tests do not lose their validity due to the creation of newer versions. Time does not invalidate tests due to the improvement of neurological methodology, such as magnetic resonance imaging. This assumption is unscientific, unproven, and if true, would discredit all older neuropsychological and neurological knowledge. In science, no method, theory, or information, once validated, loses that validation merely due to time or the creation of another test or procedure. Once validated, a procedure is only disproved or replaced by means of new research.