The Validity of Assessment Center Ratings and 16PF Personality Trait Scores in Police Sergeant Promotions: A Case of Incremental Validity

• Published date: 01 March 2007
• Author: Sarah DeArmond,Kevin G. Love
• Date: 01 March 2007
• DOI: 10.1177/009102600703600102
• Subject Matter: Article

The Validity of
Assessment Center
Ratings and 16PF
Personality Trait Scores
in Police Sergeant
Promotions:
A Case of Incremental Validity
By Kevin G. Love, Ph.D. and Sarah DeArmond, M.S.
Assessment centers (AC) have become a mainstay of promotion systems for
both the private and public sectors—police agencies included.1 While costly
to develop and implement, their track record of validity and legal defensibility
has justified their increased use.2 Similarly, the use of personality trait measurement
in personnel decisions has also shown a substantial increase in use based on its validity
in predicting a range of employee and managerial job behaviors.3 Unlike ACs, police
agencies have used personality assessment primarily for entry level officer screening
and fitness for duty assessments.4 The use of personality assessment in police officer
promotional decisions has rarely been reported.
Personality trait scores have shown incremental validity, however, when com-
bined with cognitive ability tests in predicting a range of employee and managerial
behaviors,5 but not for state police recruits.6 In addition, incremental validity has been
found for personality measures when combined with biodata7 and ACs.8 Other than
the attempt of Cortina, Coherty, Schmitt, Kaufmann and Smith,9 who found no evi-
dence of incremental validity, there have been no other reported studies of incremen-
tal validity for personality trait scores when used in combination with any other
predictor of police officer or supervisor performance.
Evidence of Assessment Center Validity
There is substantial literature which documents the validity of ACs in predicting on-
the-job performance, especially for managers.10 In addition to its proven validity, based
on candidate reactions and court challenges, the AC method has been labeled fair and
legally defensible.11
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The validity of ACs used for police officer selection and promotion has been
shown to be commensurate with that found in other organizational settings. For exam-
ple, AC performance ratings have been shown to be significantly related to supervisor
ratings of officer performance,12 valid for high ranking police officials13 and accurate
in prediction over a 19-year time span.14
Evidence of Validity for Personality Measurement
While early reviews of the literature indicated that personality assessment yielded
poor validity in predicting job performance,15 more recent work has established per-
sonality as a bona fide predictor of a range of job-related behaviors across a variety of
organizational settings and employee groups, including police officers.16 A number of
meta-analyses have provided reasonable support for the use of personality assessment
in selection.17 The decision to use personality assessment by itself within an employee
selection context should be made with caution, given the greater validity shown by
other predictor measures, such as cognitive ability tests and assessment centers.
The resurgence of personality assessment as a valid predictor of job performance
is due in large part to the fact that:
1. Personality has been shown to be a valid predictor of work-related outcomes;
2. Personality measures do not generally display adverse impact against demo-
graphic subgroups (e.g., racial, gender, ethnic, etc.);
3. The validity of personality measures is not affected by intentional faking;18 and
4. The construct of personality has become more structured with the acceptance
of the “Big Five” personality traits (e.g., conscientiousness and extraversion)
and the consistency with which they are measured.19
Many studies have dealt specifically with the ability of personality trait scores to
predict police officer performance, both on the job and while in training. Personality
traits have been measured through traditional clinical self report inventories as well
as instruments designed to assess the Big Five dimensions (e.g., the Minnesota Mul-
tiphasic Personality Inventory;20 the Inwald Personality Inventory;21 the California Psy-
chological Inventory;22 the Eyesenck Personality Inventory, the SCL-90, and the
Bender-Gestalt;23 the 16PF;24 and the NEO Personality Inventory25). Several studies
have found that particular personality traits are indicative of on-the-job police per-
formance. Fabricatore, Azen, Schoentgen and Snibbe,26 using the 16PF, found that
“aggressiveness and tough-mindedness” were consistent predictors of superior officer
performance. Measuring the Big Five personality traits of police officers, Sarchione,
Cuttler, Muchinsky and Nelson-Gray27 found conscientiousness predictive of dysfunc-
tional job behaviors while Cortina, et al.28 showed that neuroticism, agreeableness and
conscientiousness predicted academy cadet probation ratings, peer evaluations, coun-
seling cards, training ratings, grade point average and turnover. Palmatier29 demon-
strated that neuroticism and agreeableness predicted the level of patrol activity for
state troopers. Few studies, however, have examined the ability of personality assess-
ment to predict police supervisor performance.
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The Incremental Validity of Personality Trait Scores
When Used in Combination with AC Performance
Ratings
Goffin, Rothstein and Johnston30 surmised that ACs and personality trait scores meas-
ure two separate domains of psychological and behavioral constructs. Their conclu-
sion was based on the many studies that show validity for ACs and personality
measures as sole predictors of performance and the poor relationship between AC
and personality trait scores.31 Goffin et al.32 concluded that since both ACs and person-
ality traits scores predict job performance, yet AC performance and personality trait
scores are generally not highly related, when used in combination, the unique contri-
bution of each measure to the prediction equation would yield higher overall validity.
Using a sample of 68 managers, Goffin, et al.33 showed that the personality traits
of “dominance, achievement and exhibition,” as measured by the Personality Research
Form, provided incremental validity in predicting managerial performance when com-
bined with AC performance ratings. Personality trait scores were equally predictive of
performance as AC ratings. While the Goffin, et al.34 study is generalizable to generic
managerial positions, it remains to be seen whether such incremental validity exists
in predicting police supervisor performance.
The Present Study
Data were collected using a police sergeant AC consisting of five...