Over several decades, numerous researchers and scientists have devised tests to try and determine individual personality types. They have determined five main personality traits, known as the big five personality traits.
These traits include conscientiousness, agreeableness, neuroticism, openness, and extraversion. Each of these five traits can be tested for and scored from low-to-high to determine an individual’s personality [1].
The descriptions of low and high scores for each trait reflect the extreme ends of the spectrum. Typically, most people fall somewhere between low and high scores for each trait rather than at either extreme.
While some descriptions of personality may appear negative, it is likely that individuals with these characteristics also hold many positive features. Furthermore, a personality feature that may seem negative, such as rigid thinking or cynicism, may be crucial for certain types of jobs that people on the other end of the spectrum may not be suited for [2].
However, some negative traits can cause people to be at a higher risk of experiencing mental illness or causing harm to others. These traits may be the focus of professional intervention or self-reflection and self-improvement [2][3].
The five traits and their common characteristics
Conscientiousness
People who score high on the test for conscientiousness are likely to have the following characteristics:
- Hardworking
- Ambitious
- Organized
- Punctual
- Thoughtful
- Strong sense of duty
- Often well prepared
- Goal-orientated
- Determined
- Academically successful
- Resilient
- Low risk of mental illness
- Possess positive coping skills
People who score low on the test for conscientiousness are likely to have the following characteristics:
- Careless
- Inattentive
- Dislikes schedules and routines
- Procrastinates
- Poor time management
- Struggles to find purpose
- Disorganized
- Likely to quit or change jobs regularly
- Higher risk of mental illness
Agreeableness
People who score high on the test for agreeableness are likely to have the following characteristics:
- Kind
- Generous
- Trusting
- Flexible
- Good-natured
- Altruistic
- Cooperative
- Empathetic
- Enjoys helping people
- Likely to work in a healthcare profession
People who score low on the test for agreeableness are likely to have the following characteristics:
- Untrusting
- Suspicious
- Critical of others
- Irritable
- Ungiving
- Insensitive
- Competitive
- Cynical
- Detached
- Objective
- Rigid thinking
- Uninterested in the feelings or concerns of others
- More likely to work in a professional such as law
- Higher risk of mental illness
Neuroticism
People who score high on the test for neuroticism are likely to have the following characteristics:
- Anxious
- Self-conscious
- Self-critical
- Vulnerable
- Becomes stressed easily
- Often worries about things
- Emotionally labile
- Experiences mood swings
- Overthinks things
- High risk of depression
People who score low on the test for neuroticism are likely to have the following characteristics:
- Calm
- Even-tempered
- Unemotional
- Doesn’t often worry or feel stressed
- Relaxed
- Resilient
- Lower risk of anxiety and depression
Openness
People who score high on the test for openness are likely to have the following characteristics:
- Imaginative
- Creative
- Unique
- Enjoys new experiences
- Curious
- Inquisitive
- Adventurous
- Analytical
- Liberal
- Emotionally intelligent
- Might be at a higher risk of depression due to introspection
People who score low on the test for openness are likely to have the following characteristics:
- Lacks creativity
- Traditional
- Conservative
- Prefers routines
- Uncurious about new things
- Practical
- Realistic
Extraversion
People who score high on the test for extraversion are likely to have the following characteristics:
- Enjoys talking to people
- Energetic
- Active
- Excitable
- Passionate
- Affectionate
- Assertive
- Comfortable with large groups
- Energized by being around others
- Works well with others
- Finds it easy to make friends
- May be more likely to engage in risky or spontaneous activities
- Lower risk of mental illness
People who score low on the test for extraversion are likely to have the following characteristics:
- Quiet
- Unsociable
- Uncomfortable with making conversations
- Prefers to work alone
- Prefers solitude
- Unaffectionate
- Independent
- Self-controlled
- Reserved
- Finds social situations draining
- Higher risk of mental illness [1][2][3][4][5][6]
What is the history of the big five personality traits?
For many decades psychologists have researched and investigated patterns of thoughts, behaviors, and emotions in an attempt to determine specific aspects of individual personalities and their links to mental illness, academia, and professionalism [4].
Paul Costa and Robert McCrae developed the Five-Factor Model of personality, often called the Big Five. This model was based on decades of research and theories around defining and distinguishing personality traits [1].
This work is believed to have begun in the 1930s by Gordon Allport and Henry Odbert, who initially listed over 4500 traits [7]. Their list was then collated and grouped by Raymond Cattel in the 1940s, who developed a 16-item list of personality traits [8].
Many psychologists continued to explore these concepts over the following years. This includes Hans Eysenck, who spent several decades researching personality traits. Hans Eysenck went on to develop the PEN Model, which includes psychoticism, extraversion, and neuroticism [9].
His ideas were then expanded upon and developed by Costa and McCrae in the 1980s, who created the NEO Personality Inventory (NEO-PI), which included neuroticism, extraversion, and openness [10].
Many continued to explore the ideas developed by Eysenck and Costa & McCrae, with further discussions and personality theories being proposed, including additional inventories by Eysenck [11].
Costa and McCrae then went on to add agreeableness and conscientiousness to their personality inventory, thus becoming the Five-Factor Model of personality (FFM) [1]. Many psychologists agreed that the FFM was a valid and successful representation of personality, as it has been shown to be a reliable and consistent measurement tool amongst populations across the world [4].
What influences personality traits?
Several factors can influence personality traits, including genetics, environment, personal experiences, and age.
Genetics
Research indicates that personality traits are largely linked to genetics. Twin studies show that the five traits of this model are between 40-60% inherited. As such, it can be surmised that a parent who scores very high in neuroticism is likely to pass this trait on to their children [12][13].
Environment
Similarly, these traits can be learned by children when exposed to behaviors and attitudes from their parents. Using the example of neuroticism, a neurotic parent is likely to display overt behaviors that will influence their child’s experiences and perspectives. This potentially increases the likelihood of the child going on to develop these neurotic traits themselves [12][13].
Experiences
Typically, life experiences will not entirely alter a person’s personality, but certain occurrences may cause an adjustment in how a person scores in each of the five domains [2].
For example, experiencing a traumatic or life-threatening event could cause a decrease in openness and an increase in neuroticism. This person may become less willing to engage in new activities, be more rigid in their thinking or routines, and become more anxious and worried about the consequences of their actions and the behaviors of others.
Similarly, if someone experiences abuse or bullying, this could cause a decrease in extraversion and agreeableness. They may become more withdrawn, less comfortable in social situations, more suspicious and distrustful of others, and more cynical in how they view the world and others [14].
Age
It is thought that personality remains relatively consistent throughout a person’s lifetime, particularly after reaching adulthood. However, individual characteristics can change somewhat [2].
For example, studies suggest that agreeableness and conscientiousness are likely to increase as a person ages and matures, while extraversion, neuroticism, and openness can decrease [15][16].
Physical or mental illness
Several medical illnesses and injuries could cause a change in personality, including thyroid problems, dementia, urinary tract infections, and traumatic brain injury. Similarly, many mental health conditions can cause a change in personality, such as schizophrenia, bipolar disorder, personality disorders, anxiety, and depression [17].
Illnesses could cause changes in any of the five domains. For example, depression could cause a decrease in conscientiousness, extraversion, and openness. It is common for people with depression to become withdrawn, lose interest in activities and socializing, and lose motivation and functioning in academic or professional areas.
Similarly, certain types of dementia could cause a decrease in agreeableness and conscientiousness and increase neuroticism, as dementia can cause mood swings, irritability, suspiciousness, and impaired functioning and cognition.
Professional interventions
Medications and therapy for physical and mental illnesses could also cause changes in personality traits. These interventions can reduce the impact of the illness, thereby reversing any changes that the illness caused [3][17].
Additionally, some medications could cause side effects that impact personality, while some therapies may help reduce negative personality traits, such as neuroticism [13].
How reliable are personality trait tests?
Many different personality tests are available online, some of which have been created by psychologists throughout the decades of research into this topic. These tests tend to be of varying reliability, with those not based on scientific research and evidence being the least reliable.
Factors that can influence the reliability of a personality test include [2][4][18]:
- Self-reporting: Individuals completing a personality test themselves might be subjected to their own bias and be more inclined to choose personality traits they desire.
- Individual differences: People could produce very different responses to each question within the test due to aspects such as maturity and intellect, thus reducing the validity of certain results.
- Limited view of ‘personality’: Personality may not be entirely defined by a set list of traits as it is a combination of complex factors, thoughts, and behaviors that can change depending on the external environment or context.
- Cultural differences: Different cultures and nationalities may have different ways of describing or assigning certain traits and characteristics, skewing results.
The Big Five, or Five-Factor Model, is considered one of the most reliable personality trait tests. It has been tested within many communities and cultures, age groups, and genders, showing consistent and reliable results throughout [4].
Most psychologists and professionals agree that this test is reliable despite some criticism that the test is generic or inaccurate [19]. However, the Five-Factor Model continues to be used to help determine academic and professional choices and clinical decisions while also influencing research and discussions around the topic of personality [4].
- Costa, P.T., Jr., & McCrae, R.R. (1992). Revised NEO Personality Inventory (NEO–PI–R) and NEO Five-Factor Inventory (NEO–FFI) Professional Manual. Odessa, FL: Psychological Assessment Resources.
- McCrae, R.R., & Costa, P.T., Jr. (2003). Personality in Adulthood: A Five-Factor Theory Perspective(2nd ed.). Guilford Press. Retrieved from https://doi.org/10.4324/9780203428412
- Lewis, E.G., & Cardwell, J.M. (2020). The Big Five Personality Traits, Perfectionism and Their Association with Mental Health Among UK Students on Professional Degree Programmes. BMC Psychology, 8, 54. Retrieved from https://doi.org/10.1186/s40359-020-00423-3
- Grice, J.W. (Updated 2023). Five-Factor Model of Personality. Britannica. Retrieved from https://www.britannica.com/science/five-factor-model-of-personality
- Kotov, R., Gamez, W., Schmidt, F., & Watson, D. (2010). Linking “Big” Personality Traits to Anxiety, Depressive, and Substance Use Disorders: A Meta-Analysis. Psychological Bulletin, 136(5), 768–821. Retrieved from https://doi.org/10.1037/a0020327
- Chioqueta, A.P., & Stiles, T.C. (2005). Personality Traits and the Development of Depression, Hopelessness, and Suicide Ideation. Personality and Individual Difference, 38(6), 1283-1291. Retrieved from https://doi.org/10.1016/j.paid.2004.08.010
- Allport, G.W., & Odbert, H.S. (1936). Trait-Names: A Psycho-Lexical Study. Psychological Monographs, 47(1), i–171. Retrieved from https://doi.org/10.1037/h0093360
- Cattell, R.B. (1943). The Description of Personality: Basic Traits Resolved into Clusters. Journal of Abnormal and Social Psychology, 38(4), 476–506. Retrieved from https://doi.org/10.1037/h0054116
- Eysenck, H.J., & Eysenck, S.B.G. (1976). Psychoticism as a Dimension of Personality.London: Hodder and Stoughton.
- Costa, P.T., & McCrae, R.R. (1985). The NEO Personality Inventory Manual. Odessa, FL: Psychological Assessment Resources.
- van Kampen, D. (2009). Personality and Psychopathology: A Theory-Based Revision of Eysenck’s PEN Model. Clinical Practice and Epidemiology in Mental Health: CP & EMH, 5, 9-21. Retrieved from https://doi.org/10.2174/1745017900905010009
- Power, R.A., Pluess, M. (2015). Heritability Estimates of the Big Five Personality Traits Based on Common Genetic Variants. Translational Psychiatry, 5, e604. Retrieved from https://doi.org/10.1038/tp.2015.96
- McCrae, R.R., Costa, P.T., Jr, Ostendorf, F., Angleitner, A., Hrebícková, M., Avia, M.D., Sanz, J., Sánchez-Bernardos, M.L., Kusdil, M.E., Woodfield, R., Saunders, P.R., & Smith, P.B. (2000). Nature Over Nurture: Temperament, Personality, and Life Span Development. Journal of Personality and Social Psychology, 78(1), 173–186. Retrieved from https://doi.org/10.1037//0022-3514.78.1.173
- Arsova, S., Manusheva, N., Kopacheva-Barsova, G., & Bajraktarov, S. (2016). Enduring Personality Changes After Intense Stressful Event: Case Report. Open Access Macedonian Journal of Medical Sciences, 4(3), 453–454. Retrieved from https://doi.org/10.3889/oamjms.2016.083
- Srivastava, S., John, O.P., Gosling, S.D., & Potter, J. (2003). Development of Personality in Early and Middle Adulthood: Set Like Plaster or Persistent Change? Journal of Personality and Social Psychology, 84(5), 1041–1053. Retrieved from https://doi.org/10.1037/0022-3514.84.5.1041
- Roberts, B.W., Walton, K.E., & Viechtbauer, W. (2006). Patterns of Mean-Level Change in Personality Traits Across the Life Course: A Meta-Analysis of Longitudinal Studies. Psychological Bulletin, 132(1), 1–25. Retrieved from https://doi.org/10.1037/0033-2909.132.1.1
- 17. First, M.B. (Revised 2022). Personality and Behavior Changes. MSD Manuals. Retrieved from https://www.msdmanuals.com/home/mental-health-disorders/overview-of-mental-health-care/personality-and-behavior-changes
- Ferrando, P.J., & Navarro-González, D. (2021). Reliability and External Validity of Personality Test Scores: The Role of Person and Item Error. Psicothema, 33(2), 259-267. Retrieved from https://doi.org/10.7334/psicothema2020.346
- Pervin, L.A. (1999). The Cross-Cultural Challenge to Personality. In Y.-T. Lee, C.R. McCauley, & J.G. Draguns (Eds.), Personality and Person Perception Across Cultures(pp. 23–41). Lawrence Erlbaum Associates Publishers.
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Naomi Carr is a writer with a background in English Literature from Oxford Brookes University.
Morgan Blair is a licensed therapist, writer and medical reviewer, holding a master’s degree in clinical mental health counseling from Northwestern University.