Background: Disease susceptibility and drug response of individuals are presumed to be different depending on their personality traits. The Sasang typology, a traditional Korean medical typology, explains the individual differences of vulnerability to pathology and proposes guidelines for the safe and effective use of medical herbs depending on individual traits. Objective: The purpose of the present study was to evaluate psychologic and physical characteristics of Sasang types from the perspective of personality theory. Design: After determining the Sasang type of 79 college students based on the Questionnaire for the Sasang Constitution Classification, the psychologic and physical traits of each type were analyzed by the Meyers-Briggs Type Indicator (MBTI) and Bioelectrical Impedance Analysis, respectively. Results: Each of the Sasang types showed significantly different profiles based on the MBTI scores (generalized estimation equation, coefficient = 11.88, z = 2.13, p = 0.033) and could be distinctively classified based on their MBTI scores (discriminant analysis Wilks' λ = 0.611, df = 8, χ² = 36.7, p < 0.001). Subjects with the So-Eum type (Introversion and Judging) and the So-Yang type (Extroversion and Perceiving) showed contrasting psychologic features. However, they had similar anthropometric characteristics. Subjects with Tae-Eum type had relatively higher body fat mass. Conclusion: Current results demonstrated distinctive personality traits associated with Sasang types using reproducible psychometric and anthropometric instruments. With further study, the Sasang typology could serve as a scientific tool for individualized and integrative medicine.

Previous studies suggest that personality traits play an important role in academic burnout. The aim of this study was to investigate how Cloninger's temperament and character traits explain academic burnout in a highly competitive environment of medical school. A total of 184 Korean medical students participated in the survey. The Cloninger's Temperament and Character Inventory was measured around the beginning of the semester and Maslach Burnout Inventory-Student Survey at the end of the semester. The correlations and stepwise regression analysis were conducted to explain the association between personality traits and academic burnout. In addition, latent profile analysis and profile analysis were employed to distinguish and explain differences of personality traits among latent academic burnout subgroups. The higher harm avoidance of temperament and lower self-directedness and cooperativeness of character predicted the subscales of academic burnout in medical students. The Temperament and Character Inventory personality profile of high, middle, and low latent burnout subgroups were significantly different. This study showed that personality might account for the burnout level in medical education. The importance of character dimension for modulating the effects of temperament traits on academic burnout was discussed for future research.

The purpose of present study was to examine biological and psychological characteristics of people according to the Sasang typology, which is popular in Korea. We evaluated the Sasang Personality Questionnaire (SPQ) as a measure of temperament, and Body Mass Index (BMI) as a measure of the somatic properties of each Sasang type. Subjects were 2506 (877 males, 1629 females) outpatients between the ages of 20 through 70 who requested traditional medical assessment and treatment in Korea. The structural validity of the SPQ was examined and its correlation with BMI was analyzed. The SPQ and BMI measures of each Sasang type across age and gender were presented and their differences were analyzed with Analysis of Variance. Confirmatory factor analysis and path analysis identified an acceptable three-factor structure of the SPQ measuring differences in individual’s behavior, emotion, and cognition. SPQ scores (29.71 ± 1.00, 28.29 ± 0.19 and 26.14 ± 0.22) and BMI scores (22.92 ± 0.09, 25.56 ± 0.10 and 21.44 ± 0.10) were significantly (p < 0.001) different among So-Yang, Tae-Eum and So-Eum Sasang types, respectively. The results showed that the SPQ and BMI is a reliable measure for quantifying the biopsychological characteristics of each types, and useful for guiding personalized and type-specific treatment with medical herbs and acupuncture.

A systematic review of studies related to the psychological characteristics of Sasang types was conducted with the goal of delineating generalizable psychological profiles based on Sasang typology, a traditional Korean medical typology with medical herbs and acupuncture that is characterized as personalized medicine. Journal articles pertaining to Sasang typology were collected using five electronic database systems in Korea and in the USA. As a result, 64 potentially relevant studies were identified and 21 peer‐reviewed research articles that employed psychometric inventories were included. Beginning with the use of the Minnesota Multiphasic Personality Inventory in 1992, Myers‐Briggs Type Indicator, NEO‐Personality Inventory, Temperament and Character Inventory and other personality assessment tools were employed in the identified studies. Because data synthesis could not be carried out due to the heterogeneity of the studies, the present review article sought to delineate the mutual relevance of the studies based on research results pertaining to the correlation between the aforementioned psychological assessment instruments. Results of the review indicate that two super‐factors, Extraversion and Neuroticism, serve as the foundation in regards to delineating personality constructs, such that the So‐Yang type scored high on the Extraversion dimension and low on the Neuroticism dimension, while the So‐Eum type scored low on the Extraversion dimension and high on the Neuroticism dimension. The present systematic review indicates that Sasang typology shares similarities with the Western psychological tradition.

The purpose of this study was to examine the biopsychological personality profiles of traditional Korean Sasang typology based on the Temperament and Character Inventory (TCI) in a Korean adult clinical sample. A total of 97 adults completed the Korean version of the TCI. The participants were classified as one of three traditional Korean Sasang types (31 So‐Yang, 41 Tae‐Eum, 25 So‐Eum) by three specialists in Sasang typology. The seven dimensions of TCI were compared between the different Sasang types using analysis of variance (ANOVA) and profile analysis. There were no significant differences in age, gender and education across the Sasang types. The TCI profile for each of the Sasang types was significantly different (profile analysis, df = 5.038, F = 3.546, P = .004). There were significant differences in the temperament dimensions of Novelty Seeking (F = 3.43, P = .036) and Harm Avoidance (F = 5.43, P = .006) among the Sasang types. The Novelty Seeking score of the So‐Yang type (31.90 ± 9.87) was higher than that of the So‐Eum type (25.24 ± 9.21; P = .019) while the So‐Eum type (44.64 ± 8.47) scored higher on the Harm Avoidance score compared to the So‐Yang type (35.16 ± 11.50; P = .003). There were no significant differences in the temperament dimension of Reward Dependence and Persistence, and the three character dimensions of Self‐Directedness, Cooperativeness and Self‐Transcendence. Results demonstrated distinct temperament traits associated with traditional Korean Sasang types using an objective biopsychological personality inventory. With further study, the Sasang typology may lead to enhanced clinical safety and efficacy as part of personalized medicine with traditional medicine.

Objective. Sasang typology is a traditional Korean medicine based on the biopsychosocial perspectives of Neo-Confucianism and utilizes medical herbs and acupuncture for type-specific treatment. This study was designed to develop and validate the Sasang Personality Questionnaire (SPQ) for future use in the assessment of personality based on Sasang typology. Design and Methods. We selected questionnaire items using internal consistency analysis and examined construct validity with explorative factor analysis using 245 healthy participants. Test-retest reliability as well as convergent validity were examined. Results. The 14-item SPQ showed acceptable internal consistency (Cronbachs alpha=.817) and test-retest reliability (𝑟=.837). Three extracted subscales, SPQ-behavior, SPQ-emotionality, and SPQ-cognition, were found, explaining 55.77% of the total variance. The SPQ significantly correlated with Temperament and Character Inventory novelty seeking (𝑟=.462), harm avoidance (𝑟=−.390), and NEO Personality Inventory extraversion (𝑟=.629). The SPQ score of the So-Eum (24.43±4.93), Tae-Eum (27.33±5.88), and So-Yang (30.90±5.23) types were significantly different from each other (𝑃<.01). Conclusion. Current results demonstrated the reliability and validity of the SPQ and its subscales that can be utilized as an objective instrument for conducting personalized medicine research incorporating the biopsychosocial perspective.