UPSALA JOURNAL OF MEDICAL SCIENCES 2024, 129, e10349
http://dx.doi.org/10.48101/ujms.v129.10349

ORIGINAL ARTICLE

A Japanese translation of the Swedish Universities Scales of Personality
Lykke Silfwerbranda,b, Lisa Ekseliusc, Yasuharu Koikeb and Malin Gingnella,dDepartment of Medical Sciences, Uppsala University, Uppsala, Sweden; bInstitute of Innovative Research, Tokyo Institute of Technology,
Yokohama, Japan; cDepartment of Women’s and Children’s Health, Uppsala University, Uppsala, Sweden; dDepartment of Psychology,
Uppsala University, Uppsala, Swedena

ABSTRACTARTICLE HISTORY

Background: The Swedish Universities Scales of Personality (SSP) is a personality measurement tool with ashort test battery of high psychometric quality, previously not availiable in Japanese.
Methods: We translated the SSP into Japanese and administered it to 103 Japanese nationals. For 11 of
the 13 SSP scales in the Japanese version of the SSP (SSP-J11), the Cronbach’s alpha ranged from 0.50 to
0.82 with good internal scale reliability.
Results: A principal factor analysis replicated the previous work by identifying the same three principal
dimensions of Neuroticism, Aggression, and Extraversion factors.
Conclusion: The resulting three-factor SSP-J11 shows acceptable reliability and should provide informative
insights about personality traits in research and clinical practice in a Japanese context.

Received: 9 November
2023
Revised: 17 January 2024
Accepted: 17 January 2024
Published: 21 March 2024

Introduction
Personality assessment is crucial for the study of social
interactions. Short test batteries with high psychometric quality
which are based on traits thought to have neurobiologicalcorrelates are few but existing (1). Also, such reliable personality
assessment instruments that are cross-culturally translated forinternational use are scarce (1, 2).
Personality can be described as the most important features ina person’s social and emotional functioning, distinguishing
behaviors and patterns of actions (3). The differences inpersonalities can be attributed to individual traits. Personality
traits are relatively stable, consistent, and enduring individual
characteristics that can be disentangled by analysis of behaviors,
attitudes, feelings, and habits (4). Personality traits can bemeasured by specialized tools, including self-reports, structured
observations, or data collected from individuals close to the target
person. Methods for data collection could be checklists, inventories,
or opinion surveys (5). A widely used personality inventory, thefive-factor model of personality, primarily uses lexical analysis todefine traits (6). Other personality assessment inventories, such as
Eysenck’s and Sjöbring’s models, have been based on trait
dimensions with biological correlates and implications for
information processing and psychopathology (7, 8).
The Swedish Universities Scales of Personality (SSP), commonlyinterpreted as a three-dimensional personality trait assessment
inventory, can be used for clinical and non-clinical populations (9).
Currently, the SSP is available in several languages, including
English, Chinese, and Estonian (7–9), but not yet in Japanese.
CONTACT Lykke Silfwerbrand

KEYWORDS

Swedish Universities
Scales of Personality (SSP);
cross-cultural translation;
reliability; Swedish to
Japanese; personality
inventory

The construction of the SSP forerunner, the Karolinska Scales of
Personality Inventory (KSP), used concepts defined in Eysenck’s andSjöbring’s models and was developed to assess the vulnerabilitiesof psychopathology (10–12). The SSP is a shortened andpsychometrically enhanced version of the KSP. It is a shortpersonality assessment instrument that uses timeless andstraightforward language suitable for healthy people andpsychiatric patients. There is an insignificant difference in results
between female and male respondents. The test battery is a pool ofscales from which a smaller number of scales can be extracted forresearch objectives. It can also serve as a comprehensive assessment
tool for several personality traits (9). However, the SSP is often
interpreted with three factors: general neuroticism, aggression, andextraversion measures. Because the SSP is a short test andpsychometrically of high quality, it can serve as a valuable tool forvarious purposes and situations in clinical and research work.
This study has two principal aims: 1) to translate SSP into
Japanese with the meaning of each item preserved concerning
the Japanese language and culture and 2) to evaluate thereliability of the Japanese translation of the SSP.

Materials and methods
Swedish Universities Scales of Personality
SSP consists of 91 items (seven for each of the 13 scales)
describing various ways of behavior. The subscales reflect thefollowing dimensions of personality: Somatic Trait anxiety (STA),
Psychic Trait Anxiety (PsTA), Stress Susceptibility (SS), Lack oflykke.silfwerbrand@uu.se© 2024 The Author(s). Published by Upsala Medical Society.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits ­unrestricted
use, distribution, and reproduction in any medium, provided the original work is properly cited.

2 L. SILFWERBRAND ET AL.

Assertiveness (LA), Embitterment (E), Trait Irritability (TI), Mistrust(M), Verbal Trait Aggression (VTA), Physical Trait Aggression(PhTA), Social Desirability (SD), Impulsiveness (I), Adventure
Seeking (AS), and Detachment (D). For scale descriptions, see
Table 1. For each of the 91 items, there are four possible
responses: 1 = ‘Does not apply at all’, 2 = ‘Does not apply very
well’, 3 = ‘Applies pretty much’, and 4 = ‘Applies completely’. Each
reply is scored one, two, three, or four points.

EthicsThis study received ethical approval from the Tokyo Institute ofTechnology, Japan: Validation study of SSP into Japanese (dnr2018174). For analysis of the data in Sweden, this study received
ethical approval from the Swedish Ethical Review Authority (dnr2021-05482-01).

Statistical methods
Translation method
The SSP was translated from Swedish into Japanese (hereafterreferred to as the SSP-J11) and then back-translated to Swedish.
The translation process followed the specifications provided
by RAND Health Care (13). There were five translators (fourJapanese and one Swedish). All four Japanese translators have
lived in Sweden for at least 5 years and speak fluent Swedish.
All translators held academic degrees. The research group was
continually discussing changes and adaptations during theprocess. The primary focus was on reliably representing eachitem’s initial psychometric meaning and face value. Items in
the SSP-J11 were kept in the same order as in the Swedish
version.

Participants and power
Some 103 persons took part, 62 (60%) males and 41 (40%)
females (Table 2). Participants were recruited from two sources:
1) a group of 47 Japanese nationals, which were adult employees,
also taking part in another study at a large technical universityand 2) from a convenience sample of 56 Japanese technology
university students. The questions were answered in privacy
over the Internet, and all participants provided written consent
before taking part in the study.
An 80% power for the study was estimated using a two-tailed
independent one-sample t-test. An expected effect size of 0.3
with an error probability of 5% would require 90 participants. To
compensate for a potential data loss of approximately 10%,oversampling was considered with 103 participants.

For direct comparison to the original SSP publication, thesame statistical methods were applied. The data were
processed using modules and programs in Python on Jupyter(14). To compare the results with the original data, means andstandard deviations were calculated for each scale for thewhole sample, and women and men separately. T-tests
between female and male responses were calculated
scalewise for all variables. The Cronbach’s alpha for the scales
was deduced for the whole group and women and men
separately to assess internal reliability. Inter-scale correlations
were calculated to determine how closely the scales wererelated. Kaiser–Meier–Olkin (KMO) measurement was applied
to test that the proportion of variance of the items wasadequate for factor analysis. Finally, factor analysis wasderived using principal component analysis with varimax
rotation to mirror the analysis used for SSP originally (9).
Using the same setup allowed to assess whether this analysis
yielded similar factor loadings as the original data. For power
calculations, G Power software was used (15).
Table 2. Participant data for the 103 participants who answered thequestionnaire, 40% of the participants were women.
Years of age
All
Women
Men
18–29
30–39
40–49
50–59
60–69
>70
Total

29
6
14
41
11
2
103

8
1
4
20
7
1
41

21
5
10
21
4
1
62

Table 1. Descriptions of scale traits.
Scale name

Abbreviation

For persons with high scores in the respective scales, the personality traits can be
described as follows

Somatic trait anxiety
Psychic trait anxiety
Stress susceptibility
Lack of assertivenessImpulsiveness
Adventure seeking
Detachment
Social desirability
Embitterment
Trait irritability
Mistrust
Verbal trait aggression
Physical trait aggression

STA
PsTA
SS
LA
I
AS
D
SD
E
TI
M
VTA
PhTA

A tense and restless personality with autonomic disturbances
A worrying and anticipating personality that lacks self-confidence
Feeling of uneasiness when urged to speed up and easily fatigued
A personality that cannot speak up and be self-assertive in social situations
A personality that acts impulsively, without planning
A personality that avoids routine and needs action
A ‘schizoid’ personality that is withdrawn and avoids involvement with others
Personality traits that are socially conforming, friendly, and helpful
An unsatisfied personality that blames and envies others
An irritable personality that lacks patience
A suspicious personality that distrusts other people’s motives
A personality that gets into arguments and beats people when annoyed
A personality of getting into fights, starting fights, and hitting backNote. Scale descriptions from the Swedish version of the SSP (7).

JAPANESE TRANSLATION OF SSP 3

Results

Factor analysis

Descriptive statistics for the 13 scales are presented inTable 3. Mean scale results were on average 2.44, with astandard deviation of 0.519. There were no significant
differences in the t-tests between the scores of women andmen on any of the scales. (Data not shown.)

Factor analysis for correlations of the scales in the SSP-J11 wascalculated using principal component analysis and rotated tosimple structure using the Varimax method to identify factors
with eigenvalues >1 (Table 6). The KMO measurement was 0.76.
The first factor corresponded to the STA, PsTA, LA, E, and M
scales, and the second factor included SD with a negative
loading, TI, VTA, and PhTA. Two scales, I and AS, loaded on thethird factor. Thus, the first factor assesses traits of neuroticism,
the second various forms of aggression, and the third broadly
extraversion factors. The cumulative explained variance was
66%.

Internal reliability
All but two scales had a Cronbach’s alpha value of ≥0.5
(range 0.56–0.84) for the whole sample (Table 4). SS had a
Cronbach’s alpha value of 0.0091 for the whole group(women: 0.14 and men: −0.10) and D 0.18 for the wholegroup (women: −0.27 and men: 0.30). E showed a borderline
value of 0.50 (women: 0.11 and men: 0.61). Slightly higher
values were found in LA with 0.54 (women: 0.51 and men:0.57) and VTA with 0.62 (women: 0.43 and men: 0.70). These
three and the eight scales in which the Cronbach’s alpha was≥0.70 were retained for the in-depth analyses, whereas the
SS and D scales were excluded due to low internalconsistency.

Inter-scale correlation
Two inter-scale correlations in the SSP-J11 scales are equal to orslightly above 0.6 (Table 5). These include the relationshipbetween the two anxiety-prone scales (STA and PsTA) and thecorrelation between STA and E. More than 95% of the correlations
were <0.50, with 34% < 0.40. The absolute median inter-scalecorrelation was 0.44. Spearman correlation analysis renderedvery similar results, see Appendix A.
Table 3. SSP-J11 scale means and standard deviations and gender differences.
Scale name
Tot
Women
Men
SSP Tot (7)Somatic trait
anxiety
Psychic trait
anxiety
Stresssusceptibility
Lack ofassertivenessImpulsiveness
Adventureseeking
Detachment
Socialdesirability
Embitterment
Trait irritability
Mistrust
Verbal trait
aggression
Physical trait
aggression

M

(SD)

M

(SD)

M

(SD)

2.11

(0.62)

2.19(0.56)

2.05(0.66) 1.89 (0.58)

M

2.48

(0.62)

2.45(0.55)

2.50(0.67) 2.02 (0.61)

2.53(0.34)

2.59(0.33)

2.50(0.34) 2.03 (0.49)

2.43(0.48)

2.48(0.46)

2.40(0.50) 2.09 (0.57)

2.48
2.76

(0.52)(0.56)

2.54
2.72(0.22)(0.51)

2.44
2.78(0.58) 2.25 (0.52)(0.60) 2.46 (0.59)

2.51
2.86

(0.36)(0.50)

2.59
2.84(0.29)(0.49)

2.47
2.88(0.40) 2.09 (0.53)(0.51) 2.87 (0.40)

2.45
2.30
2.44
2.31

(0.44)(0.54)(0.60)(0.49)

2.48
2.29
2.45
2.30

(0.32)(0.59)(0.64)(0.41)

2.43
2.31
2.43
2.32

(0.51) 1.80
(0.51) 2.35
(0.58) 1.98
(0.54) 2.17

2.11

(0.68)

2.05(0.65)

2.15(0.71) 2.05 (0.65)(SD)(0.50)(0.56)(0.53)(0.54)

SSP: Swedish Universities Scales of Personality; SD: standard deviation.

Discussion
Our results show that a translated and reduced version of the
SSP, ‘SSP-J11’, may be reliable to use in a Japanese context. Theinternal reliability of the two subscales SS and D was however
not acceptable.
In line with the original SSP, the SSP-J11 was interpreted as athree-factor model solution, which is constructed based on
psychopathological and psychobiological theories (9, 10, 16,17). The common scales of the SSP and the SSP-J11 have very
similar loadings. The neurobiological underpinnings ofpersonality traits are an area of active research. Since theestablishment of the Swedish version of the SSP and its
predecessors, some individual traits have been possible to linkto neurobiology. Trait neuroticism has been linked to low
serotonin uptake activity (18, 19), and low platelet monoamineoxidase activity has been associated with traits, such as
extraversion (12, 20, 21). Aggression traits have been indicatedto have genetic sources and relate to low activation of the MAOA
gene (22, 23). However, more research is needed, and thetranslated version of the SSP into the SSP-J11 now allows for thispossibility in a Japanese context.
The Cronbach’s alphas for the 11 scales in the SSP-J11 haveacceptable values (range 0.50 to 0.82), which are similar to the
Swedish version (range 0.59 to 0.84). Eight out of the 11 scales
have alpha values ≥0.7. Three more with values of 0.5–07 werealso deemed acceptable since there is a small number of itemsin the scales (24). 95% of the inter-scale correlations are <0.50,
and median intercorrelations are 0.44, indicating moderatecorrelation and acceptable reliability (25). Based on previous
research using other scales, trait anxieties are likely rated higher
by women and trait aggression higher by men (26, 27), but thepresent study could not detect such gender differences. Basedon the power of this study, we cannot draw any firm conclusion
about gender differences but we note that our results in this
aspect are similar to those reported for the Swedish version of
the SSP, that is, no observed gender differences. The SSPJ-11 hasa middling KMO measurement of its proportion of variance,
making factor analysis relevant. Taken together, the replicationof the three-factor solution together with the low inter-scalecorrelation indicates that the SSP-J11 scales are reliable also in
the Japanese context.

4 L. SILFWERBRAND ET AL.

Table 4. Cronbach’s α of the Japanese and Swedish versions of the SSP.
Scale name
Cronbach’s α (95% Cl)
Cronbach’s α women(95% Cl)

Cronbach’s α men(95% Cl)

Cronbach’s α Swedish
version of the SSP (7)Mean inter-itemcorrelation of the SSP (7)Somatic trait anxiety
Psychic trait anxiety
Stress susceptibility
Lack of assertivenessImpulsiveness
Adventure seeking
Detachment
Social desirability
Embitterment
Trait irritability
Mistrust
Verbal trait aggression
Physical trait aggression

0.79 (0.70, 0.86)
0.84 (0.77, 0.90)−0.0049 (−0.44, 0.34)
0.57 (0.38, 0.71)
0.75 (0.65, 0.84)
0.79 (0.70, 0.86)
0.27 (−0.05, 0.52)
0.70 (0.58, 0.80)
0.61 (0.44, 0.74)
0.64 (0.48, 0.76)
0.79 (0.70, 0.86)
0.70 (0.57, 0.80)
0.86 (0.79, 0.90)

0.75
0.82
0.74
0.78
0.73
0.84
0.77
0.59
0.75
0.78
0.78
0.74
0.84

0.31
0.40
0.28
0.33
0.28
0.42
0.32
0.17
0.30
0.34
0.34
0.29
0.43

0.75 (0.67, 0.82)
0.82 (0.76, 0.87)
0.058 (−0.25, 0.31)
0.54 (0.40, 0.67)
0.70 (0.61, 0.78)
0.75 (0.67, 0.82)
0.15 (−0.13, 0.38)
0.70 (0.60, 0.78)
0.50 (0.33, 0.63)
0.70 (0.60, 0.78)
0.81 (0.75, 0.86)
0.62 (0.50, 0.72)
0.84 (0.79, 0.86)

0.69 (0.52, 0.82)
0.78 (0.67, 0.87)
0.13 (−0.34, 0.49)
0.51 (0.24, 0.71)
0.57 (0.33, 0.74)
0.68 (0.51, 0.81)−0.22 (−0.34, 0.49)
0.68 (0.51, 0.81)
0.071 (−0.44, 0.45)
0.78 (0.66, 0.87)
0.85 (0.76, 0.91)
0.43 (0.11, 0.66)
0.82 (0.72, 0.89)

SSP: Swedish Universities Scales of Personality; CI: confidence interval.
Table 5. Correlation matrix for the SSP-J11 scales.
STA
PsTA
LA
STA
PsTA
LA
I
AS
SD
E
TI
M
VTA
PhTA

–
0.60***
0.38***
0.10−0.010−0.28**
0.61***
0.53***
0.49***
0.26**
0.27**–
0.58***−0.11−0.050−0.19
0.59***
0.39***
0.48***−0.0680.12–−0.060−0.10−0.16
0.37***
0.31**
0.39***−0.17−0.046

I

AS

SD

E

TI

M

VTA

PhTA

–
0.43***
0.087
0.13
0.086
−0.091
0.028
0.076

–
0.38***
0.12−0.046
0.061
−0.11
0.042

–
−0.24*−0.45***−0.27**−0.30**−0.28**–
0.45***
0.47***
0.26**
0.37***–
0.50***
0.51***
0.47***–
0.20*
0.28**–
0.59***–

STA: Somatic trait anxiety; PsTA: Psychic trait anxiety; LA: Lack of assertiveness; I: Impulsiveness; AS: Adventure seeking; SD: Social desirability; E: Embitterment;
TI: Trait irritability; M: Mistrust; VTA: Verbal trait aggression; PhTA: Physical trait aggression.
*p < 0.01, ** p < 0.001, ***p < 0.0001.
Table 6. Principal factor analysis with varimax rotation of the 11 scales in
the SSP-J11.
Scale Name
Abbrevations Factor 1
Factor 2
Factor 3
Somatic trait anxiety
Psychic trait anxiety
Lack of assertivenessImpulsiveness
Adventure seeking
Social desirability
Embitterment
Trait irritability
Mistrust
Verbal trait
aggression
Physical trait
aggression
Eigenvalue

STA
PsTA
LA
I
AS
SD
E
TI
M
VTA

0.74
0.87
0.77
−0.0070
0.037
−0.24
0.72
0.52
0.67
−0.0490.33−0.053−0.23
0.13−0.082
−0.51
0.33
0.64
0.27
0.88

0.066
−0.091
−0.16
0.75
0.87
0.48
0.20
−0.040−0.030−0.036

PhTA

0.12

0.80

0.11

3.9

1.8

1.6

Note. The bottom row shows the eigenvalues > 1 of the factors.
Bold scale values indicate which factor the scale is loading on.

Introducing a new cross-culturally reliable personality
assessment instrument offers unique research and clinical work
opportunities, but generalizing personality tests across cultures
can also be challenging. Translations need to sustain theconceptual meaning and psychometric equivalence for items in
different cultural settings (2, 28). The low Cronbach’s alphavalues for the scales SS and D may derive from such translationand cultural difficulties. Despite our efforts to translate theinitial meaning of every item and respect cultural differences,
the items of these two scales may have been interpreted
differently in Japan and Sweden. In these two scales, the shortquestions may describe the situation too vaguely for theJapanese context, making them difficult to interpret. For
example, Gustavsson et al. (9) depicted persons with high SS
scores as ‘Easily fatigued, feeling uneasy when urged to speed
up’. The scale includes such items as ‘I easily feel pressure when
told to speed up my work’. (仕事のスピードを上げるように言われるとすぐストレスを感じてしまう。/ Jag blir lättstressad när jag uppmanas att skynda på med ett arbete.) and ‘I
think I have less energy than most people I know’. (ほとんどの知りあいに比べて，自分は活力が少ない方だと思う。/ Jag
tycker att jag orkar mindre än de flesta i min bekantskapskrets.).
Stress level has been reported as higher and more diverse in theJapanese context, which can ultimately influence the level ofadditional stress one can sustain1 (29). The world value survey
1. Personal dialogue with professional translator of Japanese to Swedish,Yukiko Duke, in February 2022.

JAPANESE TRANSLATION OF SSP 5

also notes that the freedom of choice and control is estimatedhigher among Swedish people than Japanese World Values
Survey Association, 2021 (30). Taken together, the items related
to the pressure to sustain stress may need to be assessed
differently in the two cultures. Similarly, the low reliability for D
could be due to different cultural contexts and too vaguely
posed questions.2 Gustavsson et al. (9) described personalities
with high D scores as ‘Avoiding involvement in others,
withdrawn’. D includes items such as ‘I feel uncomfortable whenpeople take me into their confidence’ (人に心を許されると居心地悪く感じる。/ Jag känner mig besvärad då folk kommer
till mig med personliga förtroenden.) and ‘I prefer not to get
involved in other people’s problems’. (できれば，他人の問題に首をつっこみたくない。/ Jag föredrar att slippa engagera
mig i andra människors problem.) Describing oneself on a scale of
D may be more uncomfortable in the Japanese than in the
Swedish context, especially as the expected personal distance isgenerally reported larger in Japan than in western cultures(29–32). Hence, in analogy with the discussion about SS, thestatements in SSP may not be sufficiently fine-tuned to capture
the essence of D within the Japanese context. However, the powerof the current study does not allow for detailed analyses of isolated
items. Future studies with larger sample sizes are warranted toelucidate the mechanisms for the low reliability of D and SS.
A limitation of the study is that the participants (employed,
mostly middle-aged, adults, and students of technology) may
not represent the general Japanese population. Also, although
the study has at least 80% power for a small to medium effectsize with a 5% error probability, it could be on the small side
for some effects, such as gender differences. In addition, thesample size does not allow for analyses on the level ofindividual items in accordance to the COSMIN risk of bias
checklist (33, 34), but this translation of SSP should anyway be
relevant on scale and factor levels.
Based on this study, the reliability of the SSP-J11 seems
acceptable on the level of scales and factors and may be used
for clinical work and research in a Japanese setting. The SSPJ-11
inventory in Japanese can be supplied from the corresponding
author.

Data accessibility
The translation of the SSP into Japanese, SSPJ-11, is available foracademic purposes from the corresponding author. The analysis
code for this study can be supplied from the corresponding
author, but the materials are not available. This study was notpreregistered.

Acknowledgments
Keiko Fune and Kiyo Wada have contributed with valuablecomments to the translation of the SSP. Yukiko Duke has
provided insight into the differences between Swedish and
2. Personal dialogue with professional translator of Japanese to Swedish,Yukiko Duke, in February 2022.

Japanese cultures and languages. Lars von Knorring has
contributed with valuable comments to the manuscript.

Notes on contributors
Conceptualization was made by LS, LE, and MG. All authors
contributed to the methodology and project administration. LS
carried out the formal analysis and wrote the initial draft, and all
authors reviewed and edited the final version.

Funding
This study was supported by CriseLess AB, Sweden, by financing
the first author’s time. CriseLess AB had no influence over any
part of the study, and the authors are alone responsible forcontent and writing of the manuscript.

Disclosure statement
The authors have no conflict of interest to disclose.

ORCID
Lykke Silfwerbrand https://orcid.org/0000-0003-1512-8202
Lisa Ekselius https://orcid.org/0000-0002-5760-7730

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JAPANESE TRANSLATION OF SSP 7

Appendix A
Table 1. Spearman’s correlation analysis of the SSP-J11 scales.
STA
PsTA
LA
I
STA
PsTA
LA
I
AS
SD
E
TI
M
VTA
PhTA

–
0.62***
0.42***
0.12−0.0028−0.24*
0.63***
0.48***
0.49***
0.20*
0.22*

–
0.54***−0.09
0.0014−0.19*
0.59***
0.38***
0.45***−0.0480.13–−0.010−0.10−0.24*
0.35***
0.32***
0.38***
−0.10
0.021

–
0.36***
0.053
0.13
0.13
−0.11
0.068
0.0036

AS

SD

E

TI

M

VTA

PhTA

–
0.33***
0.15−0.052
0.033
−0.13
0.024

–
−0.27**−0.44***−0.24*−0.28**−0.22*–
0.46***
0.45***
0.25**
0.36***–
0.45***
0.50***
0.42***–
0.20*
0.30**–
0.53***–

STA: Somatic trait anxiety; PsTA: Psychic trait anxiety; LA: Lack of assertiveness; I: Impulsiveness; AS: Adventure seeking; SD: Social desirability; E: Embitterment;
TI: Trait irritability; M: Mistrust; VTA: Verbal trait aggression; PhTA: Physical trait aggression.
*p < 0.01, ** p < 0.001, ***p < 0.0001.