Running personality assessments on candidates yourself: what works and what to avoid

Yes, within some clear limits

You can use personality assessments in your own hiring without a consultant, and many small companies do. The tool has to be built and documented for selection, it has to relate to the job you are filling, and you have to treat the results as one input alongside skills, references and a structured interview, never as a pass-fail gate. Get those three things right and an assessment can sharpen your judgment. Get them wrong and it adds false confidence, and possibly legal risk.

I studied personality psychology in Texas A&M's industrial and organizational psychology program, and personality-based recruiting is the core of my work at Wayne Human Capital in Dallas. I am happy to see owners use data in hiring, because it beats resumes and gut instinct alone. This guide covers what you can do yourself, the mistakes I see most, and the point where it makes sense to get help. It is general information from my experience, not legal advice.

What an owner can do well without help

Most of the value in assessment-based hiring comes from the discipline around the test, not the test itself. These are steps any owner can take on their own, and they improve hiring even before you pick a tool.

If you do only the first three items on this list, you will already be ahead of most companies your size, because you will be hiring against a defined target instead of a feeling.

• Write a role profile that describes the behaviors that succeed in the job and on your team, not just the tasks.
• Describe what your best current performers have in common in how they communicate, decide and handle pressure.
• Use the same structured interview questions for every candidate and score answers against the role profile.
• Give any assessment to every finalist for the same role, at the same stage, in the same way.
• Use assessment results to choose follow-up interview questions, not to rank candidates by score.
• Keep results confidential and limited to the people making the decision.

Choosing a tool that was actually built for hiring

This is where do-it-yourself testing most often goes wrong. Many popular personality tools were designed for self-awareness, team building or coaching, and they were never meant to compare candidates. The best-known example is the Myers-Briggs Type Indicator. Its publisher, The Myers-Briggs Company, has stated that it does not condone using the MBTI for any sort of hiring or selection, because it was not designed for that purpose.

Free online quizzes are a bigger problem still, because there is usually no documentation at all about what they measure or whether results hold up. When you evaluate a tool, ask the vendor for its technical documentation: what traits it measures, how it was developed, and what evidence connects it to job performance. If a vendor cannot or will not answer, move on.

Keep in mind that a vendor's documentation does not transfer responsibility. The U.S. Equal Employment Opportunity Commission's guidance on employment tests says the employer is still responsible for making sure its tests are valid for the jobs they are used for.

The legal lines to know before you test

Federal anti-discrimination laws apply to employment tests, including personality tests. The EEOC's guidance explains that tests must not be used to discriminate based on race, color, religion, sex, national origin, disability or age, and that a neutral test which disproportionately screens out a protected group can be challenged unless it is job-related. Which federal laws cover you depends partly on headcount, which I explain in the hiring rules that switch on as a Texas company grows.

The disability rules deserve special attention. Under the EEOC's guidance on pre-employment medical examinations, an employer generally cannot require medical examinations before making a conditional job offer, and a psychological test counts as medical if it provides evidence that would lead to identifying a mental disorder. A test designed and used to measure only things such as honesty, tastes and habits is not medical. In plain terms: tools built to diagnose mental health conditions do not belong in the pre-offer stage of hiring.

If you are unsure whether a particular tool or practice is appropriate for your company, talk to an employment attorney before you use it. That conversation costs far less than defending a hiring decision later.

Reading a report without reading too much into it

Even a good assessment report can mislead an untrained reader. The most common error is treating a description of tendencies as a prediction of behavior in every situation. People adapt, and the same trait can be a strength in one role and a friction point in another.

Read the report against your role profile, not against an ideal person. Then use what it raises to plan interview questions. If a report suggests a candidate prefers working independently and your role requires constant collaboration, ask about times they worked in a tightly coordinated team and how it went. The interview answer, checked against references, is what you decide on.

Be especially careful with results that confirm what you already believed about a candidate. It is natural to give those more weight than results that surprise you, and that is exactly how an assessment turns into a tool for justifying a gut decision rather than testing it.

• Compare results to the role profile, not to yourself or your favorite employee.
• Look for patterns across several traits rather than reacting to one score.
• Turn each concern into a specific behavioral interview question.
• Check what you learned with references from former managers.
• Write down why you hired or passed, so you can learn from the outcome later.

A simple sequence for your next hire

If you want to try this on your next opening, here is the order I would follow. It keeps the assessment in its proper place, after the target is defined and before the final decision, and it gives you a record you can learn from when you look back on the hire a year later.

Expect the first time through to feel slower than your usual process. The second time is faster, because the role profile and interview questions can be reused and refined.

• Define the role profile, including the behaviors that succeed on your team.
• Write structured interview questions tied to that profile, with a simple scoring guide.
• Screen resumes for the skills and experience the job truly requires.
• Hold a first interview with the same questions for every candidate.
• Give the same documented assessment to each finalist at the same stage.
• Use the results to plan second-interview questions, then check references with former managers.
• Decide, and write down why, so you can compare the reasoning to the outcome later.

Where do-it-yourself testing tends to break down

When owners show me an in-house process that is not working, it is usually for one of a handful of reasons. None of them is about intelligence or effort. They come from using a precise instrument without the training it assumes. The good news is that each one is easy to correct once you can see it, and most owners recognize at least one on this list from their own process.

• Using a team-building or self-awareness tool to choose between candidates.
• Setting a cutoff score and rejecting people automatically.
• Testing some candidates and not others, or testing at different stages.
• Hiring people whose results look like the owner's own, which narrows the team.
• Skipping the role profile, so there is nothing to compare the results against.
• Letting the report replace the interview instead of shaping it.

Signs it is time to bring in someone trained

Doing it yourself works best for routine roles, a stable team and an owner willing to learn the discipline. It also works best when you hire often enough to build a feel for how results relate to performance on your own team, which is hard to develop from one hire a year. It is worth getting help when the stakes rise or the pattern of mis-hires keeps repeating despite the process.

Specifically, consider outside help for a key seat such as a first manager or a leadership role, when your last two or three hires in the same area did not last, when good people are leaving and you are not sure why, or when you are growing quickly and the culture has never been put into words. In those situations, the value is less in the test and more in interpretation and in understanding the team the person is joining. My guide on whether personality tests are accurate enough for hiring explains what that interpretation adds.

A middle path: train your managers once

Many owners do not need me to run every search. They need their managers to know how to select for fit, and then they can handle most hiring themselves. That is what my personality-based hiring workshops are for. A workshop teaches owners and leadership teams to define the behaviors that succeed on their team, build role profiles, run structured interviews and use assessment data responsibly.

If you are still deciding how much weight fit should carry against experience, read culture fit versus skills and experience first. And if you are here because the last hire went wrong, why the resume fooled you explains the pattern. I work with companies across Dallas–Fort Worth and remotely, and I am glad to tell you whether a workshop, a single search or neither is the right next step.

Questions people ask me