Why Teams Are Turning to Personality Assessments
The most effective teams don't succeed because every member thinks alike — they succeed because they leverage cognitive diversity deliberately. Research from McKinsey's organizational health studies indicates that high-performing teams demonstrate approximately 35% better personality-diversity balance than underperforming teams. This isn't about hiring "the right personality" — it's about assembling complementary personalities that cover each other's blind spots.
Personality assessments give hiring managers and team leaders a shared language for understanding these differences. When a team knows that their project manager is a high-C DISC type who needs detailed documentation, while their creative lead is a high-I who needs verbal brainstorming, they can adapt their communication rather than attributing differences to incompetence or bad faith.
What Should You Measure? Choosing the Right Assessment
Different assessments measure different things, and choosing the wrong tool for your goal is one of the most common mistakes organizations make.
DISC for Communication and Team Dynamics. The DISC model measures four behavioral styles: Dominance (direct, results-driven), Influence (enthusiastic, collaborative), Steadiness (patient, reliable), and Conscientiousness (analytical, detail-oriented). DISC is ideal for team workshops because it's intuitive, non-judgmental (no style is "better"), and directly actionable for daily communication. Try the free DISC assessment on JobCannon.
Big Five for Job Fit and Performance Prediction. The Big Five (OCEAN) model measures Openness, Conscientiousness, Extraversion, Agreeableness, and Neuroticism on continuous scales. It's the most scientifically validated personality framework, with decades of meta-analytic research linking specific traits to job performance. Conscientiousness alone shows correlations of r=0.22-0.27 with performance across virtually all job categories. Try the free Big Five assessment on JobCannon.
EQ (Emotional Intelligence) for Leadership Assessment. Emotional intelligence measures the ability to perceive, understand, manage, and use emotions effectively. EQ is particularly valuable for assessing leadership candidates, client-facing roles, and positions that require navigating complex interpersonal dynamics. Research by Goleman and others consistently links high EQ with leadership effectiveness. Try the free EQ assessment on JobCannon.
The Legal Framework: EEOC Guidelines and Compliance
Using personality assessments in employment decisions carries legal obligations that every hiring manager must understand. The Equal Employment Opportunity Commission's Uniform Guidelines on Employee Selection Procedures (1978) establish that any assessment used in employment decisions must meet three criteria:
Job relevance. The assessment must measure characteristics that are demonstrably related to the specific job's requirements. You can't require a high Extraversion score for a data analyst role, for example, unless you can document why Extraversion is essential for that particular position.
Non-discrimination. The assessment must not disproportionately screen out members of protected classes (race, gender, age, disability, religion, national origin) unless the screening criteria are directly job-related and consistent with business necessity.
Validation. The assessment must have published psychometric evidence demonstrating its reliability (consistent results over time) and validity (actually measuring what it claims to measure). Proprietary assessments without published validation data are legally risky.
Organizations using personality assessments for hiring should document their rationale for each assessment, demonstrate the job-relevance connection, and apply the assessment consistently across all candidates for the same role.
Best Assessments for Hiring: What the Research Says
Big Five variants are the gold standard for employment selection. Meta-analyses by Barrick and Mount (1991) and subsequent replications consistently show that Big Five traits predict job performance across role categories. Conscientiousness is the strongest universal predictor (r=0.22-0.27), while other traits predict performance in specific role types — Extraversion predicts sales success, Agreeableness predicts service role performance, and Emotional Stability predicts performance under pressure.
Avoid MBTI for hiring decisions. This is not a criticism of the MBTI as a self-development tool — it's a statement about psychometric validity for employment selection. The Myers-Briggs Foundation itself states that the MBTI should not be used for hiring. SHRM (Society for Human Resource Management) echoes this guidance. The MBTI's test-retest reliability is insufficient for employment decisions, and it was designed to promote self-understanding, not predict job performance.
DISC is excellent for post-hire team development but should not be used as a selection filter. Its value is in helping existing team members understand and adapt to each other's communication styles, not in screening candidates in or out.
Team Composition: Building Personality-Diverse Teams
Using the DISC framework as a practical example, the most effective teams have representation from all four styles:
D (Dominance) members drive decisions, set pace, and push through obstacles. Without D-style members, teams deliberate endlessly without action. With too many D-styles, teams experience power struggles and rushed decisions.
I (Influence) members build enthusiasm, facilitate communication, and maintain team morale. Without I-style members, teams become dry and disconnected. With too many I-styles, teams generate energy without substance.
S (Steadiness) members provide stability, support implementation, and ensure follow-through. Without S-style members, teams start many things and finish few. With too many S-styles, teams resist necessary change.
C (Conscientiousness) members maintain quality standards, catch errors, and ensure thoroughness. Without C-style members, teams produce sloppy work. With too many C-styles, teams suffer analysis paralysis.
A well-composed team has at least one strong representative of each DISC style, with the team leader aware of the team's personality map and actively managing the dynamics that arise from style differences.
How to Run a Team Personality Workshop
Here's a practical framework for a two-hour team personality session that produces lasting results:
Phase 1 — Individual Assessment (15 min, pre-work). Have each team member complete the DISC and/or Big Five assessment before the workshop. Send results to participants with a brief guide on interpreting their profiles. Emphasize that no style is better than another.
Phase 2 — Results Sharing (30 min). In a facilitated group setting, each team member shares their primary style, one strength they recognized in their results, and one blind spot they want the team to help them manage. The facilitator models vulnerability by sharing first.
Phase 3 — Team Mapping (30 min). Plot the entire team's results on a visual map (DISC quadrant or Big Five spider chart). Identify where the team is heavy (multiple members in one quadrant) and where it's light (no members in a quadrant). Discuss what the imbalances mean for the team's performance patterns.
Phase 4 — Action Planning (30 min). Based on the team map, identify three specific communication adjustments the team will implement. For example: "Before making major decisions, we'll give our C-style members 24 hours to review the data" or "We'll start meetings with a 5-minute check-in to meet our I-style members' connection needs."
Follow-up (2 weeks later). Reconvene briefly to review whether the communication adjustments are working and refine as needed.
Red Flags: What Not to Do with Personality Tests
Even well-intentioned organizations make mistakes with personality assessments. Watch for these red flags:
Rejecting candidates based solely on personality test results without documented job-relevance justification is both legally risky and practically foolish. Test results should inform decisions, not make them.
Requiring personality tests before a conditional job offer is restricted in some jurisdictions and is generally considered a best-practice violation. Personality assessments work better as post-offer, pre-start onboarding tools or as team development instruments for existing employees.
Using unvalidated or proprietary assessments without published psychometric data exposes organizations to legal challenges. If the test publisher cannot provide reliability coefficients, validity studies, and adverse impact analyses, choose a different instrument.
Allowing test results to override demonstrated skills and experience in hiring decisions contradicts the purpose of personality assessment. Tests provide one data point among many — they should never be the sole deciding factor.
Free Team Assessment with JobCannon
JobCannon offers free personality assessments that teams can use for both individual self-development and collective team mapping. Have your team take the DISC assessment for communication insights, the Big Five test for trait-based understanding, and the Emotional Intelligence assessment for leadership development. All results are instant, no signup required, and your data stays private.
For hiring managers who want to implement personality-informed hiring responsibly, start by identifying the three most important personality traits for each role you hire, then select a validated assessment that measures those specific traits. Document your rationale, apply the assessment consistently, and always use results as one input among many in your hiring decisions.