Assessment centers for personnel selection: strengths, inconsistencies, and best practices

Topic: Assessment

Publication: Human Resource Management Review (September, 2009)

Article: Validity of assessment centers for personnel selection

Authors: Thornton, G. C., & Gibbons, A.M.

Reviewed By: Bobby Bullock

Assessment centers (ACs) have been used to aid the process of external and internal selection of employees and high potentials, certification, and promotion for over 50 years.  At ACs, multiple assessors observe the behavior of assesses as they engage in organizational simulations designed to test their ability to perform new, relevant assignments.  Historically, overall assessment ratings (OARs) and dimensional scores have been shown to predict a range of relevant selection outcomes.

Compared with other selection tools (such as cognitive ability or personality), ACs are stronger predictors of future effectiveness.  OARs have been found to predict promotion rates, salary progress, job performance ratings, performance in training, and other performance criteria.  ACs exhibit less group bias (in terms of sub-group differences) compared to cognitive ability test scores, but their fairness should not be blindly assumed.  Also, although the use of an AC can be fairly expensive, their overall utility is positive.  In fact, some studies have found the value of using an AC can range from thousands of dollars per hire to over 1 million overall!

Although ACs have been found to be generally effective and worthwhile, research over the past few decades has highlighted various controversies and conflicting
recommendations.  Thornton and Gibbons (2009) have suggested that more research needs to be undertaken in order to shed some light on various issues such as:  which type of dimensions to assess (i.e., cognitive, interpersonal, etc.), the use of dimension-based ACs vs. exercise-based ACs (which they believe depends on the target position), participant impression management and faking, and how to integrate ratings from multiple raters and exercises.  However, the authors noted that certain best practices can improve the AC process.  These include:

  • Highly trained assessors (using psychologists is particularly effective
  • Clear and easy to use assessment tools
  • Use of exercises identified through thorough job analysis to be relevant to the target job

Proper thought given to:  the participant rating system, insight into the variance of possible responses to exercises, and even the very instructions given to participants

Not all hope is lost!  The authors summarized their findings best by stating that “research and practice suggest that ACs are valid, fair, legally defensible, and acceptable to candidates and other stakeholders in a wide variety of jobs” (Thornton & Gibbons, 2009, p. 183).

Thornton, G. C., & Gibbons, A. M. (2009).
Validity of assessment centers for personnel selection. Human Resource Management Review, 19(3), 169-187.