Personnel diagnostics: Well-founded personnel decisions through objective procedures

At a time when the battle for the best talent is becoming ever more intense, HR managers face a central challenge: How do I find the right employees who not only fit professionally but also have the potential to be successful in the company in the long term? The answer lies in the Personnel diagnostics. But what exactly is behind this term? And how can they be achieved in such a way that decisions are fair, efficient and scientifically based?

This article highlights personnel diagnostics from the basics to the most modern digital approaches and shows why they are essential for sustainable recruiting.

What is personnel diagnostics? A definition

Personnel diagnostics is a branch of applied psychology and business administration. It includes the systematic recording of the characteristics, abilities and personality traits of people in order to make well-founded decisions in the HR sector. The aim is to make predictions about professional success, the fit to the workplace or the development of employees.

It is not about putting people in boxes, but about getting as objective and comprehensive a picture of their strengths, potential and preferences as possible. This can be done both as part of personnel selection (e.g. when filling a vacant position), in personnel development (e.g. when planning continuing education measures) or in personnel consulting.

Aptitude diagnostics vs. personnel diagnostics: These terms are often used interchangeably, but there is a subtle difference. Aptitude diagnostics is a sub-area of personnel diagnostics. It focuses explicitly on the question of how well a person is suited for a particular job. Personnel diagnostics has a wider range of applications and also includes topics such as team analysis, potential analysis or psychological inventory analysis of employees.

The importance of personnel diagnostics in modern recruiting

In many companies, personnel decisions are still based heavily on the gut feeling of recruiters and managers. But the human factor poses a high risk of subjective errors, so-called Cognitive Biases or even perceptual distortions. Classic job interviews, certificates or simple resume checks can reinforce these unconscious prejudices. For example, the halo effect (one positive property outshines all others), the anchor effect, or the availability heuristic can lead to incorrect decisions.

Personnel diagnostics addresses this problem by focusing on scientific quality criteria Set:

• Objectivity: Independence of results from the person who performs the procedure.
• Reliability: reliability; similar results should be achieved when the test is repeated under the same conditions
• Validity: Validity; the process actually measures what it is intended to measure (e.g. suitability for a particular role).

Only by complying with these criteria can an objective and fair selection of personnel be ensured.

From interviews to algorithms: The most important instruments of personnel diagnostics

The instruments of personnel diagnostics are diverse and range from classic to cutting-edge approaches. The choice of the right procedure depends on the aim of the diagnosis and the position to be filled.

• Classic instruments:
  
  • Structured interview: In contrast to a free interview, all applicants are asked the same questions in a fixed order. This increases objectivity and comparability.
  • Biographical questionnaire: Record past life and experiences in order to draw conclusions about future behavior.
  • Work samples: Applicants solve tasks that come directly from everyday working life. This has a high predictive power for subsequent success.
• Modern testing methods:
  
  • Personality tests: These tests, based on psychological models such as the Big Five, measure individual personality traits. They are particularly relevant to assess the fit with corporate culture or a team.
  • Situational Judgement Tests (SJTs): Hypothetical situations from everyday working life are presented and applicants should decide how they would react. This provides information about social skills and judgment.
  • Game-based assessments (GBAs): An innovative approach that uses playful elements to capture cognitive abilities, personality traits, and behaviours. These procedures are intuitive, barrier-free and make the process significantly more attractive for applicants. Read more about game-based assessments in our detailed article.
• Complex processes:
  
  • Assessment Center (AC): Applicants go through various exercises and simulations in groups or individually. Observers evaluate competencies such as the ability to work in a team, leadership or problem solving.
  • Potential analyses: The aim here is to predict the future performance of employees and to derive suitable development measures.

Finally, it is crucial to look holistically at future skills. In a rapidly changing world of work, traditional methods are losing relevance, as the World Economic Forum's “Future of Jobs Report 2025" clearly shows that reading, writing and arithmetic remain basic skills, but are no longer among the most important skills of the future. Instead, analytical and creative thinking, curiosity, resilience and technological competence are required. However, many traditional instruments are unable to adequately capture these future skills, which is why a look at modern testing methods is unavoidable.

The role of DIN 33430: Scientific standards in practice

In order to ensure the quality of personnel diagnostics procedures, Germany has the DIN 33430. It sets quality standards for the development, application and evaluation of job-related aptitude assessment procedures. For companies, the application of DIN 33430 means:

• Higher legal certainty: Decisions are based on valid and objective principles.
• Better predictive power: The likelihood of hiring the right person is increasing.
• Increased fairness: All applicants are assessed according to the same criteria.

Compliance with this standard is an important seal of approval for reputable providers of diagnostic procedures and gives recruiters the assurance that they are using scientifically sound and legally correct methods.

Modern Approaches: Rethinking Personnel Diagnostics

Sticking to traditional methods alone will inevitably lead to the problems described above: high costs, time-consuming processes and, above all, the risk of making the wrong personnel decisions due to unconscious perceptual distortions.

Digitalization offers a decisive way out here by enabling efficient and at the same time scientifically based personnel diagnostics that eliminate the human factor and its sources of error. Aivy uses cutting-edge psychological approaches with an intuitive digital platform.

This is how Aivy solves the central problems of personnel diagnostics:

• Scientific basis and quality criteria: The assessments were developed in close collaboration with scientists and are demonstrably reliable and valid. Compliance with DIN 33430 is a core development principle. [Link to DIN 33430 white paper]
• Objectivity and bias reduction: Through standardized, automated evaluations, the results are independent of the HR manager or the personal relationship with the candidate. Subjective impressions and unconscious prejudices have no influence.
• Efficiency and scalability: Diagnostics can be carried out anywhere and at a flexible time. The evaluation is carried out in real time, which massively speeds up the recruiting process — even with large numbers of applicants.
• Positive candidate experience: The games are entertaining, intuitive and increase the positive application process experience by 33%. At the same time, 9 out of 10 applicants find Aivy better than traditional selection processes. As a result, more applicants are reached and dropout rates are reduced.

Practical example: The change in recruiting at Lufthansa Group

Large companies such as the Lufthansa Group are also facing challenges that are relevant for many companies — from SMEs to corporations. They were looking for an opportunity to modernize their selection process for trainee recruiting. They wanted to move away from rigid, paper-based tests towards an attractive, digital process that also appeals to young talent.

Aivy delivered just that: a standardized, digital and automated process. The playful assessments measured applicants' competencies based on data and delivered measurable results that revolutionized the previous manual process and the existing tool:

• Higher quality: The accuracy rate for the aptitude assessment was impressive 96% — long before the first personal contact took place. Compared to the previous, less valid in-house tool, Aivy drastically minimized the risk of incorrect decisions.
• Massive efficiency: The evaluation of the assessments was immediately available. The process was completed at over 100 minutes per application accelerates. This allowed HR teams to focus on the human component and the interview instead of spending time on administrative tasks.

Better acceptance: The completion rate for online assessments rose to 86%, as the modern, interactive approach inspires applicants. In contrast to the rigid, less appealing in-house solutions, Aivy ensured a positive candidate journey and increased the attractiveness of the employer brand.

Lufthansa's example shows how scientifically based and technologically advanced personnel diagnostics can increase the quality of selection and at the same time massively scale the process — a solution that adapts seamlessly to the needs of every company and surpasses even existing systems.

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Conclusion: Personnel diagnostics as a strategic success factor

Personnel diagnostics is much more than just a theoretical concept. It is a strategic tool for making the right personnel decisions in a dynamic working world. By using scientifically based processes, companies can not only minimize the risk of incorrect appointments, but also increase their fairness and attractiveness as employers.

A digital platform such as Aivy bridges the gap between scientific standards and practical applicability. It enables companies of all sizes to carry out objective, efficient and positive personnel diagnostics that are up to the challenges of modern recruiting.

Would you like to find out how Aivy can optimize your recruiting?

Frequently asked questions (FAQ)

1. Is personnel diagnostics also relevant for small and medium-sized enterprises (SMEs)? - - Absolutely. For SMEs in particular, incorrect staffing is often associated with high costs. The use of digital and scalable solutions makes scientific personnel diagnostics accessible and affordable even for smaller companies.
2. What is the difference between personnel diagnostics and an aptitude test? - An aptitude test is a form of personnel diagnostics. Personnel diagnostics is the overarching term that includes the systematic recording of characteristics for various purposes (selection, development, advice), while the aptitude test focuses specifically on assessing suitability for a specific position.
3. What psychological models are behind modern tests? - Many modern tests are based on recognized psychological models such as Big Five (to measure personality traits), Cattell intelligence theory or other models for recording specific cognitive abilities.
4. How can digital tools like Aivy make personnel diagnostics fair and objective? - Digital tools standardize the entire process. All candidates are given the same tasks, under the same conditions. The evaluation is carried out using a fixed algorithm, which eliminates any unconscious prejudices on the part of recruiters.
5. Is data processed in personnel diagnostics in accordance with data protection regulations? - Reputable providers strictly comply with legal data protection regulations (e.g. GDPR). Sensitive data is encrypted and processed anonymously.
6. What does DIN 33430 say? - DIN 33430 is a German standard that sets minimum standards for the development, use and evaluation of job-related aptitude assessment procedures. It serves to ensure quality in aptitude diagnostics and helps to make fair and objective decisions.

sources

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