Different jobs call for different abilities. A well-known best practice for hiring people is to perform a thorough job requirements analysis that documents which skills and abilities are necessary for the job. But when it comes to discovering exactly which qualities best predict job success for a particular role at your organization, knowing where to start can be a challenge.
Pre-employment tests can help with this process: in fact, one of the best strategies to find the right talent for your team is by first testing your current employees.
The technical term for this process is a local validity study, which is essentially a way to measure how successful a pre-employment test is at predicting success for a particular role in a specific organization. It’s a “local” study because it focuses in on your organization. And because most professionally developed pre-employment tests are already extensively validated, local validity studies serve as an extra layer of validity providing immediate insight into the value of the test for your particular company.
So how exactly does a local validity study work in practice? Let’s imagine you’re hiring sales executives who will be responsible for selling a fairly complex product. Cognitive aptitude tests and personality tests are a common choice for this type of position, so you administer the two tests to your existing sales executives. Next, you would compare your employees’ test scores on both tests with a measure of their job performance to make sure the test scores correlate with the business outcomes you value, and to identify any specific qualities that are most predictive of success.
It’s a pretty simple concept, but there are a few key things to remember when conducting a study like this. First, you need to be able to administer the test to a decent sample of people in order for your findings to have statistical merit. The bigger the sample size the better; you're unlikely to come up with any statistically significant finding unless the sample is at least 25 people, and preferably more.
Second, if you’re going to be comparing your employees’ test scores with their performance, you have to have in place a way to meaningfully measure performance within your organization. This can include anything from performance ratings to sales numbers, as long as management can agree internally that these performance metrics are accurate. If you can’t trust your performance metrics, you can’t trust the study.
Speaking of performance metrics, you need to have some range in performance ratings in order to see meaningful results. For example, if your chosen metric is an employee rating out of 5, and every employee received somewhere between 4 and 5, it will be difficult to see any correlation when the range of performance is so narrow. This is a classic example of what statisticians call a range restriction problem.
To get the best results in a local validity study, it’s recommended that you test a wide sample of employees in the position you’re hiring for, not just top performers. At first glance, it makes sense to only test the best employees so that you can directly identify the attributes you want in your candidates. But if you don’t test your mid to low performers, you won’t actually know for sure that your top performers would have scored higher than them on the test. Performing the study with all of your employees in that position gives you a clearer window into the test’s association with job performance.
Your current team is a powerful resource. Harnessing that resource can help you uncover the skills and abilities to search for when growing your team. Administering tests to your current employees before you begin searching for candidates allows you to better understand your team’s strengths and to construct blueprints for future hires.
