<Table> <Tr> <Td> </Td> <Td> This article needs attention from an expert in statistics . Please add a reason or a talk parameter to this template to explain the issue with the article . WikiProject Statistics may be able to help recruit an expert . (November 2008) </Td> </Tr> </Table> <Tr> <Td> </Td> <Td> This article needs attention from an expert in statistics . Please add a reason or a talk parameter to this template to explain the issue with the article . WikiProject Statistics may be able to help recruit an expert . (November 2008) </Td> </Tr> <P> Validity is the extent to which a concept, conclusion or measurement is well - founded and corresponds accurately to the real world . The word "valid" is derived from the Latin validus, meaning strong . The validity of a measurement tool (for example, a test in education) is considered to be the degree to which the tool measures what it claims to measure; in this case, the validity is an equivalent to accuracy . </P> <P> In psychometrics, validity has a particular application known as test validity: "the degree to which evidence and theory support the interpretations of test scores" ("as entailed by proposed uses of tests"). </P>

The degree to which a test actually measures what it supposed to measure