Predictive Validity in Psychology: Definition & Examples

Definition of Predictive Validity in Psychology

When developing assessment tools, validity is crucial. In general, validity refers to how well a test or assessment actually measures what it intends to measure.

So, if you were completing a survey designed to measure your level of affinity for chocolate, you would expect the results to provide you and the assessment administrator with information related to how much you enjoy chocolate, right? It sounds simple enough, but often, other unexpected variables can interfere and impact how well the assessment measures what it intends to measure.

For example, if you really love to eat chocolate, but you have an allergy to it, questions about how often you eat chocolate alone might not accurately measure your level of affinity for chocolate. You may love chocolate, but if your allergy prohibits you from eating it, then an assessment that relies on that type of question would not be considered a valid assessment of chocolate affinity.

Predictive validity is a specific type of validity that helps to address the question, 'Does this assessment measure what it is intended to measure and can the results be used to predict things about the participants?' As the name implies, predictive validity addresses how well a specific tool predicts future behavior.

Predictive validity is determined by calculating the correlation coefficient between the results of the assessment and the subsequent targeted behavior. The stronger the correlation between the assessment data and the target behavior, the higher the degree of predictive validity the assessment possesses. Conversely, a weak correlation between the assessment data and the target behavior indicates low levels of predictive validity.

Example

Let's look at an example to help explain predictive validity in a more practical context.

It's pretty common for employers to ask applicants to complete a personality assessment as part of the application process for employment. It might not always seem obvious to the applicant, but many online applications will include a series of questions designed to assess a variety of personality traits. Let's use the personality trait of conscientiousness as an example. Since conscientiousness is positively correlated with things like honesty, timeliness, and good organization skills, it makes sense that employers would want to hire people with those traits.