Validity and reliability in assessment methods

For example, an employer interested in understanding how well a personality test identifies individuals that are likely to engage in counterproductive work behaviors might compare applicantsвЂ™ personality test scores to how many accidents or injuries those individuals have on the job, if they engage in on-the-job drug use, or how many times they ignore company policies. So how can we tell if an assessment predicts performance? Assessment scores must be statistically evaluated against a measure of employee performance. Criterion-Related ValidityДЄn assessment demonstrates criterion-related validityВ if the results of the assessment areВ predictive ofВ a function thatвЂ™s related to job performance. Ensuring that an assessment demonstrates content validity means judging the degree to which test items and job content match each other. While the executive is probably required to type sometimes, this skill is not as nearly as important to performing that job as it would be for the executive secretary. HereвЂ™s an example: aВ fast typingВ speed would likely be considered a key part of the job for an executive secretary, but not for an executive. Content ValidityДЄn assessment is said to have content validityВ when the criteria itвЂ™s measuring aligns with and adequately covers the content of the job.В Also, the extent to which that content corresponds with success on the jobВ is part of the process in determining how well the assessment demonstrates content validity. There are severalВ ways for assessment companies to measure types of validity within tests, including content, criterion-related, and construct validity. In pre-employment assessments, this means predicting the performance of employees or identifying top talent. There are many ways to determine that an assessment is valid В validity in researchВ refers to how accurate a test is, or, put another way, how well it fulfills the function for which itвЂ™s being used. For example, if part of a pre-employment assessment is designed to measure math skills, test-takers should score equally as well on the first and second halves of that part of the test.ДЄВ validity definitionВ is a bit more complex because itвЂ™s more difficult to assess than reliability. Internal consistencyВ focuses elsewhere to confirm that, yes, test items that are intended to be related are truly related.ДЄssessment companies typically measure internal consistency by correlating scores on theВ first half of the test to those on the second half.В Since these scores should be measuring the same thing, the correlation should be 0.7 or higher. Since no test is going to be completely error-free, the correlation needs to be 0.7 or higher to be considered reliable. Researchers then measure the correlation coefficient-a statistical measure ranging on a scale from 0, no correlation, to 1, perfect correlation, to assess the reliability of the test. With this type,В the same group of people is given the test twice (a few days or weeks apart) in order to spot differences in results. To confirm a testвЂ™s reliability,В assessment companiesВ determine consistency over time with test-retest reliability. To determine the reliability of their tests, assessment companies pay close attention to two aspects of reliability in particular: re-test reliability and internal consistency measures.ДЇind out why science-based hiring assessments are more helpful at identifying candidatesвЂ™ potential than resumes, referrals, and interviews here. So,В if youвЂ™re focusing on the reliability of a test, the question to ask is: are the results of the test consistent? If someone takes the test today, a week from now, and a month from now, will their results be the same? If the results are inconsistent, the test is not considered reliable. HereвЂ™s a good definition ofВ reliability in a research context: if an assessment is reliable, the results will be very similar no matter when someone takes the test. Of the two terms, assessment reliability is the simpler concept to explain and understand.

Validity and reliability in assessment methods