Search Results (79)

Introduction/Objective: Patient satisfaction with nursing care quality is an important patient-reported indicator of hospitalization experience. Previous studies have mainly examined sociodemographic, clinical, and organizational factors, while personality traits have rarely been included in explanatory models. This study examined the association of sociodemographic characteristics, hospitalization-related variables, and personality traits with patient satisfaction. Methods: A single-center cross-sectional study was conducted among hospitalized patients in a general hospital in Croatia. Data were collected at discharge using a demographic and hospitalization questionnaire, the NEO Five-Factor Inventory, and the Croatian version of the Patient Satisfaction with Nursing Care Quality Questionnaire. Group differences were analyzed using non-parametric tests, and hierarchical regression analysis was performed. Results: Younger age, employment, male gender, and better self-rated health were associated with higher satisfaction. Patients admitted on a scheduled basis and those staying alone or with one other person in the room were more satisfied. Sociodemographic variables explained 21.5% of the variance in satisfaction (R² = 0.215; adjusted R² = 0.168). After hospitalization-related variables were added, the explained variance increased to 30.1% (R² = 0.301; adjusted R² = 0.232). The addition of personality traits further increased the explained variance to 45.6% (R² = 0.456; adjusted R² = 0.385). In the final model, staying with two or more persons was negatively associated with satisfaction, whereas agreeableness and conscientiousness were positively associated with satisfaction. Conclusions: Patient satisfaction with nursing care quality was associated with patient characteristics, hospitalization conditions, and personality traits. Accommodation conditions and individual psychological differences should be considered when interpreting satisfaction as an indicator of nursing care quality. Full article

This study examines whether Drawmetrics (DM), an expressive–semantic personality system, can be linked with the Five-Factor Model (Big Five) through an embedding-based mapping approach and network psychometric methods. A total of 185 participants completed both the DM assessment and the IPIP-NEO 120 Big Five inventory. DM term outputs were embedded using a miniLM sentence-transformer and aggregated into 30 facet composites, with six composites per domain. Big Five facet composites were extracted from standardized reports and harmonized to canonical facet names. Analyses focused on the overlap sample (N = 148) with valid scores on both instruments. DM composites demonstrated strong internal structure and high stability indices. Substantial semantic-space alignment was observed between DM term language and Big Five facet language, supporting interpretable linking. However, person-level correlations between DM and Big Five domains were modest (mean |r| ≈ 0.07; Spearman similar), with the largest facet-level association at |r| ≈ 0.26. DM appears to represent a coherent expressive–semantic trait space that is related to, but not isomorphic with, Big Five traits. These findings support a linking rather than equivalence interpretation and highlight the need for future research on scaling, reliability, range restriction, and criterion validation. Full article

Background: Sleep disorders, particularly insomnia, represent a significant health concern in medical education. Neuroticism, characterized by emotional instability and stress reactivity, shows cross-sectional associations with sleep disturbances in healthcare trainees. Limited research examines these relationships among South Asian medical students. This cross-sectional study investigated insomnia symptom prevalence, personality correlates, and environmental factors among Pakistani medical students. Methods: We conducted a cross-sectional study among 364 undergraduate medical and dental students in Peshawar, Pakistan (June–November 2024). Data collection occurred during examination months. Data collection employed validated instruments: the Insomnia Severity Index (ISI) and the NEO Five-Factor Inventory neuroticism subscale (NEO-FFI-12). Statistical analyses included Pearson correlations, chi-square tests, and multivariate regression with interaction terms. Results: Among 364 participants (mean age 21.3 ± 2.3 years, 52.2% female), 47.0% reported severe insomnia symptoms (ISI 22–28), with 89.0% experiencing at least subthreshold symptoms (ISI ≥ 8) during the 2-week assessment period. These prevalence rates reflect symptom severity over a 2-week period during examination months and do not represent clinical diagnoses of chronic insomnia disorder, which requires ≥3 months of symptoms with clinical confirmation. High neuroticism (NEO-FFI ≥ 37) characterized 59.8% of students. Multivariate regression revealed a robust cross-sectional association between neuroticism and insomnia symptom severity (β = 0.239, 95% CI [0.173, 0.305], standardized β = 0.342, p < 0.001) and may reflect measurement during peak examination stress rather than stable trait-outcome relationships. Hostel residents showed non-significantly higher clinical insomnia prevalence than day scholars (75.9% vs. 67.5%, p = 0.081). Clinical-year students demonstrated significantly lower insomnia severity than pre-clinical students (β = −1.271, p < 0.001), a finding that contradicts assumptions about increasing stress through training progression. The neuroticism × living arrangement interaction was non-significant (p = 0.118); however, post hoc power analysis indicated the study was underpowered to detect small moderation effects, making this finding inconclusive. Conclusions: This study documents high insomnia symptom severity during a 2-week assessment period in Pakistani medical students, with a robust cross-sectional association with neuroticism. However, these findings must be interpreted within the constraints of the cross-sectional design, which cannot establish temporal precedence or causality between neuroticism and insomnia symptoms. These symptom prevalence rates likely reflect a combination of chronic sleep disorders and transient examination-related stress. Living arrangements showed small, non-significant associations with insomnia. The observed association between neuroticism and insomnia may be partially mediated or confounded by unmeasured variables, including academic stress, psychiatric comorbidities, substance use, and other sleep disorders. Findings suggest potential benefits from interventions addressing cognitive-emotional factors, though comprehensive diagnostic assessment is needed to distinguish chronic insomnia disorder from transient, stress-related sleep difficulties. Longitudinal research with objective sleep measures, structured psychiatric assessment, and systematic confounder evaluation is essential to establish causal relationships and intervention efficacy in this population. Full article

Background/Objectives: Personality traits influence motivation, self-regulation, and adaptation in high-performance sports, and are partially modulated by dopaminergic genetic variability. This study aimed to examine the association between the DRD2 Ex8 rs6276 polymorphism and NEO Five-Factor Inventory (NEO-FFI) personality traits in elite athletes and non-athlete controls. Methods: A total of 323 participants were included: 141 athletes and 182 controls. Genomic DNA was isolated from venous blood, and DRD2 Ex8 rs6276 genotypes (A/A, A/G, G/G) were determined using real-time PCR with melting-curve analysis. Personality traits were assessed using the NEO-FFI, and group differences as well as genotype × group interactions were evaluated using multivariate analyses and non-parametric tests. Results: Athletes scored significantly higher on Conscientiousness than controls. A genotype × group interaction was observed for Extraversion, and the main effect of the genotype was found to be Agreeableness. Athletes with the A/A genotype exhibited the highest Extraversion scores, whereas those with the G/G genotype demonstrated higher Agreeableness than other genotypes. Conclusions: These findings indicate that dopaminergic variation contributes to individual differences in social and motivational traits, which may support athletic engagement and adaptation to high-demand environments. The results should be interpreted with caution due to the moderate sample size, deviation from the Hardy–Weinberg equilibrium in the athlete group, and reliance on a single personality assessment tool. Full article

Background: Claustrophobia is defined as the fear of enclosed spaces, and it is a rather common specific phobia. Although the Claustrophobia Questionnaire (CLQ) is a valid questionnaire to measure claustrophobia, there have been no studies validating this tool in Greek. Thus, our aim was to translate and validate the CLQ in Greek. Methods: We applied the forward–backward translation method to translate the English CLQ into Greek. We conducted confirmatory factor analysis (CFA) to examine the two-factor model of the CLQ. We examined the convergent and divergent validity of the Greek CLQ by using the Fear Survey Schedule-III (FSS-III-CL), the NEO Five-Factor Inventory (NEO-FFI-NL-N), and the Spielberger’s State-Trait Anxiety Inventory (STAI). We examined the convergent validity of the Greek CLQ by calculating Pearson’s correlation coefficient between the CLQ scores and scores on FSS-III-CL, NEO-FFI-NL-N, STAI-S (state anxiety), and STAI-T (trait anxiety). We examined the divergent validity of the Greek CLQ using the Fisher r-to-z transformation. To further evaluate the discriminant validity of the CLQ, we calculated the average variance extracted (AVE) score and the Composite Reliability (CR) score. We calculated the intraclass correlation coefficient (ICC) and Cronbach’s alpha to assess the reliability of the Greek CLQ. Results: Our CFA confirmed the two-factor model of the CLQ since all the model fit indices were very good. Standardized regression weights between the 26 items of the CLQ and the two factors ranged from 0.559 to 0.854. The convergent validity of the Greek CLQ was very good since it correlated strongly with the FSS-III-CL and moderately with the NEO-FFI-NL-N and the STAI. Additionally, the Greek CLQ correlated more highly with the FSS-III-CL than with the NEO-FFI-NL-N and the STAI, indicating very good divergent validity. The AVE for the suffocation factor was 0.573, while for the restriction factor, it was 0.543, which are both higher than the acceptable value of 0.50. Moreover, the CR score for the suffocation factor was 0.949, while for the restriction factor, it was 0.954. The reliability of the Greek CLQ was excellent since the ICC in test–retest study was 0.986 and the Cronbach’s alpha was 0.956. Conclusions: The Greek version of the CLQ is a reliable and valid tool to measure levels of claustrophobia among individuals. Full article

Background: Preparing patients for surgery considers assessing the patient’s somatic health, for example by the American Society of Anesthesiology (ASA) scale or the Revised Cardiac Risk Index (RCRI), known as the Lee index. This process usually ignores mental functioning (personality and anxiety), which is known to influence health. The purpose of this study is to analyze the existence of a relationship between personality traits (the Big Five model and trait-anxiety) and anesthesia scales (ASA scale, Lee index) used for the preoperative evaluation of patients. Methods: The study group comprised 102 patients (59 women, 43 men) scheduled for hip replacement surgery. Patients completed two psychological questionnaires: the NEO-FFI (NEO Five Factors Inventory) and the X-2 STAI (State-Trait Anxiety Inventory) sheet. Next, the presence and possible strength of the relationship between personality traits and demographic and medical variables were analyzed using Spearman’s rho rank correlation coefficient. Results: Patients with a high severity of trait anxiety are classified higher on the ASA scale (rs = 0.359; p < 0.001). Neuroticism, defined according to the Big Five model, significantly correlates with scales of preoperative patient assessment: the ASA classification (rs = 0.264; p < 0.001) and the Lee index (rs = 0.202; p = 0.044). A hierarchical regression model was created to test the possibility of predicting ASA scores based on personality. It explained more than 34% of the variance and was a good fit to the data (p < 0.05). The controlled variables of age and gender accounted for more than 23% of the variance. Personality indicators (trait anxiety, neuroticism) additionally accounted for slightly more than 11% of the variance. Trait anxiety (Beta = 0.293) proved to be a better predictor than neuroticism (Beta = 0.054). Conclusions: These results indicate that inclusion of personality screening in the preoperative patient evaluation might help to introduce a more individualized approach to patients, which could result in better surgical outcomes. Full article

Brain-derived neurotrophic factor (BDNF) is associated with nicotine use behaviours, the intensity of nicotine cravings, and the experience of withdrawal symptoms. Given the established influence of sex, brain-derived neurotrophic factor variants, personality traits and anxiety levels on nicotine use, this study aimed to conduct a comprehensive association analysis of these factors within a cohort of women who use nicotine. The study included 239 female participants: 112 cigarette users (mean age = 29.19, SD = 13.18) and 127 never-smokers (mean age = 28.1, SD =10.65). Study participants were examined using the NEO Five-Factor Inventory and the State–Trait Anxiety Inventory. Genotyping of rs6265, rs10767664, and rs2030323 was performed by real-time PCR using an oligonucleotide assay. We did not observe significant differences in the distribution of either genotype or allele of rs6265, rs10767664 and rs2030323 between groups. However, compared to the never-smokers, cigarette users scored significantly lower on the Agreeableness (5.446 vs. 6.315; p = 0.005767; d_Cohen’s = 0.363; η² = 0.032) and the Conscientiousness (5.571 vs. 6.882; p = 0.000012; d_Cohen’s = 0.591; η²= 0.08) scales. There was significant linkage disequilibrium between all three analysed polymorphic variants—between rs6265 and rs10767664 (D′ = 0.9994962; p < 2.2204 × 10⁻¹⁶), between rs6265 and rs2030323 (D′ = 0.9994935; p < 2.2204 × 10⁻¹⁶) and between rs10767664 and rs20330323 (D′ = 0.9838157; p < 2.2204 × 10⁻¹⁶), but the haplotype association analysis revealed no significant differences. While our study did not reveal an association between the investigated brain-derived neurotrophic factor polymorphisms (rs6265, rs10767664 and rs2030323) and nicotine use, it is essential to acknowledge that nicotine dependence is a complex, multifactorial phenotype. Our study expands the current knowledge of BDNF ’s potential role in addictive behaviours by exploring the understudied variants (rs10767664 and rs2030323), offering a novel contribution to the field and paving the way for future research into their functional relevance in addiction-related phenotypes. The lower Agreeableness and Conscientiousness scores observed in women who use nicotine compared to never-smokers suggest that personality traits play a significant role in nicotine use in women. The observed relationship between personality traits and nicotine use lends support to the self-medication hypothesis, suggesting that some women may initiate or maintain nicotine use as a coping mechanism for stress and negative affect. Public health initiatives targeting women should consider personality and psychological risk factors in addition to biological risks. Full article

Background and Objectives: Evidence regarding how dispositional traits, antenatal anxiety, substance use, and obstetric events converge to shape post-partum depression (PPD) in South-East Europe is limited. We analysed 102 third-trimester women and followed them to six weeks post-partum, and 102 age-matched community controls were used to (i) compare baseline psychological profiles, (ii) chart antenatal-to-post-partum symptom trajectories, and (iii) build an integrated model of clinically relevant PPD (Edinburgh Post-natal Depression Scale, EPDS ≥ 12). Materials and Methods: All 96 raw variables were forward–backward translated from Romanian, reconciled, and harmonized. The principal instruments used were EPDS, State–Trait Anxiety Inventory form Y (STAI-Y), Revised Obsessive–Compulsive Inventory (OCI-R), NEO Five-Factor Inventory (NEO-FFI-60), and the four-item Maternal Worry and Satisfaction Scale (MWSS). Results: Groups were age-matched (31.1 ± 5.4 vs. 30.3 ± 5.1 years, p = 0.268) but differed in urban residence (39% vs. 17%, p = 0.001) and current substance use (smoking 21% vs. 34%, p = 0.041; alcohol 6% vs. 22%, p = 0.002). Of five personality domains, only openness scored lower in peripartum women (26.1 ± 4.6 vs. 29.3 ± 5.2, p < 0.001). State anxiety rose significantly from pregnancy to puerperium (+5.1 ± 8.4 points, p < 0.001). Post-partum EPDS correlated most strongly with state anxiety (r = 0.62) and neuroticism (r = 0.50). A final model (pseudo-R² = 0.30) identified post-partum state anxiety (OR 1.10 per point, 95% CI 1.05–1.15, p < 0.001) as the independent predictor; neuroticism showed a trend (OR 1.08, p = 0.081). Obstetric factors (prematurity, birth weight, caesarean section) were not significant. Conclusions: In this Romanian cohort, heightened state anxiety—in synergy with high neuroticism and lower openness—dominated the risk landscape of early onset PPD, whereas delivery mode and neonatal status were neutral. Routine perinatal mental health screening should therefore incorporate anxiety metrics alongside depression scales and brief trait inventories to refine preventive targeting. Full article

Background: Personality traits, particularly Conscientiousness, are recognised as crucial psychological factors contributing to success in elite-level athletes. Emerging evidence suggests that individual differences in these traits are influenced by environmental exposure and genetic variation, especially within the dopaminergic system. The DRD2 promoter polymorphism rs1799732, which affects dopamine D2 receptor expression, may modulate goal-directed behaviour and self-regulation traits. Methods: This study included 323 participants (141 elite mixed martial arts (MMA) athletes and 182 non-athlete controls). Participants completed the NEO Five-Factor Inventory (NEO-FFI). Genotyping for the DRD2 rs1799732 polymorphism was conducted using real-time PCR. Group comparisons and two-way ANOVA were used to assess genotype–phenotype associations and gene × environment interactions. Results: Athletes scored significantly higher on Conscientiousness than controls. A significant main effect of the DRD2 rs1799732 genotype and a genotype × group interaction were observed for Conscientiousness. Specifically, athletes with the ins/ins genotype exhibited the highest levels of Conscientiousness, whereas individuals with the del/del genotype showed the lowest scores. No significant associations were found for other personality traits. Conclusions: These findings suggest that the DRD2 promoter polymorphism rs1799732 moderates the expression of Conscientiousness, particularly under the structured and demanding conditions experienced by elite athletes. Our results support a gene × environment interaction model, highlighting the importance of considering genetic predispositions in high-performance environments. These insights may inform personalised psychological support strategies tailored to athletes’ genetic profiles, enhancing motivation, self-regulation and long-term athletic development. Full article

Background/Objectives: Some haematologists share the perception that patients with Hodgkin’s lymphoma (HL) behave and manifest emotional expressions in a characteristic way. Previous research suggested a unique personality profile in HL patients compared to the general population. This study aimed to analyse and compare the personality traits of HL and NHL patients to identify potential differences. Methods: In this cross-sectional, descriptive, multicentre and replicative study, we included patients with HL and NHL from the Spanish Group of Lymphoma (GELTAMO). Personality traits and other psychosocial variables were compared between these two groups and the reference population. We used a semi-structured interview to collect demographic and psychosocial variables, and the NEO Five-Factor Inventory to assess personality traits. Results: Our findings indicate that HL and NHL patients share similar personality profiles, suggesting that the perceived differences do not stem from personality factors. Significant differences were only observed in age (HL > NHL; age: p = 0.003). These results led us to propose a new explanatory hypothesis centred on ageism. Conclusions: Our results confirm that the personality profiles of patients with any type of lymphoma are consistent with each other and with those found in the broader cancer patient population, indicating that differences observed by clinicians might be due to perceptual biases. Age, as a differentiating factor between these patient groups, suggests ageism as a potential underlying cause of these biases. Further research is required to explore the clinical implications of such stereotypical perceptions among patients that could ultimately lead to issues with patient–provider relationships and patient safety. Full article

Previous research indicates that choir singing enhances mental well-being. This study explores whether these well-being benefits are related to the personality traits of singers. We assessed the personality traits of 760 German amateur choral singers (205 men, 555 women, mean age 47.1 ± 14.0 years) using a 30-item version of the NEO–Five–Factor Inventory and compared them with a representative population sample. General mental well-being was measured with the WHO-5 well-being index, and perceived mental health benefits from singing were evaluated using the Bochum Change Questionnaire (BCQ-2000). Regression analyses examined the relationship between personality traits, BCQ-2000, and WHO-5 well-being scores. Choral singers scored significantly higher than the general population on extraversion, openness to experience, and agreeableness. The WHO-5 scores of choir singers were significantly positively correlated with extraversion and conscientiousness, and negatively with neuroticism. BCQ-2000 scores were significantly positively associated with extraversion, openness, and agreeableness. In this exploratory study, we examined the association between personality traits and singing-related mental well-being without accounting for other potential sociodemographic confounders of mental health, such as socioeconomic status. The study suggests that the self-reported mental well-being benefits of singing are influenced by individual personality traits. Full article

Objectives: In the present study, we aimed (i) to describe the personality traits of a cohort of post-COVID-19 condition (PCC) patients compared with a healthy control (HC) group, (ii) to evaluate the relationship between sleep quality and personality traits, and (iii) to investigate whether this relationship differs according to disease severity. Methods: We included 599 participants from the Nautilus Project (ClincalTrials.gov IDs: NCT05307549 and NCT05307575) with an age range from 20 to 65 years old. Of 599 participants, 280 were nonhospitalized (mild PCC), 87 were hospitalized (hospitalized PCC), 98 were in the PCC-ICU, and 134 were in the HC group. We assessed sleep quality with the Pittsburgh Sleep Quality Index (PSQI) and personality traits with the NEO Five-Factor Inventory (NEO FFI). Results: We found that mild-PCC patients had higher scores of neuroticism than HCs (p < 0.001) and ICU-PCC patients did (p = 0.020). The higher the neuroticism score was, the higher the total PSQI score (B 0.162; p < 0.001), the worse the sleep latency (B 0.049; p < 0.001), the greater the degree of sleep disturbance (B 0.060; p < 0.001), the greater the use of sleeping medication (B 0.035; p = 0.033), and the greater the incidence of daytime disturbances (B 0.065; p < 0.001) among the PCC patients. High neuroticism is also an indicator of worse sleep quality in mild-PCC (t = 3.269; p 0.001) and hospitalized-PCC (t = 6.401; p < 0.001) patients and HCs (t = 4.876; p < 0.001) but not in ICU-PCC patients. Conclusions: Although neuroticism affected sleep quality in both the PCC patients and HCs, the clinical implications and magnitude of the relationship were more significant in the PCC group. Specific and multidimensional interventions are needed to treat sleep problems in this population, and the influence of their personality traits should be considered. Full article

Variations within the serotonin transporter gene, SLC6A4 (solute carrier family 6 member 4), particularly the 5-HTTLPR (serotonin-transporter-linked promoter region), have been extensively studied in relation to behavioral and psychological traits. The aim of our study is to examine the relationship between the 5-HTTLPR polymorphism located in the SLC6A4 gene and personality traits, as assessed using the NEO-FFI (NEO Five Factor Inventory). The MANOVA model demonstrated a significant overall association, accounting for approximately 8% of the variance in the data (Wilk’s λ = 0.847, F_10,342 = 2.979, p = 0.0013, η² = 0.08). Subsequent ANOVAs revealed statistically significant 5-HTTLPR polymorphism associations with the Neuroticism (p = 0.0018, R² = 0.070), Openness (p = 0.0364, R² = 0.037), and Conscientiousness (p = 0.0020, R² = 0.068) dimensions. The post-hoc analysis revealed that individuals with the LL genotype obtained significantly lower Neuroticism scores compared to the S/S (p = 0.0011) and SL genotype (p = 0.0086) carriers. Similarly, individuals with the L/L genotype had lower Openness scores compared to those with SS genotype (p = 0.0107). LL and SL genotype carriers had higher Conscientiousness scores compared to those with the SS genotype (p = 0.0004 and p = 0.0109, respectively). In conclusion, our study provides further data regarding the implications of 5-HTTLPR polymorphism in the complex genetic architecture of human personality. The observed associations with Neuroticism, Openness, and Conscientiousness, while modest in effect size, contribute to our understanding of how genetic variation at the SLC6A4 locus may subtly shape individual personality differences. Full article

Low health literacy (HL) is associated with numerous negative health behaviors and outcomes, making it crucial to understand its underlying determinants. While associations between sociodemographic variables and subjective HL have already been demonstrated, data on the association between HL and personality remain limited. This study aims to extend the current knowledge by exploring how personality traits influence HL, beyond the effects of sociodemographic variables on HL. A cross-sectional study was performed with a sample of 238 healthy participants aged 50 to 92 years. Personality was measured using the NEO Five-Factor Inventory and subjective health literacy using the HLS-EU-Q47 questionnaire. Descriptive and correlational analyses as well as a multiple linear regression analysis with the Big Five personality traits, sex, age, and education as predictors of subjective health literacy were performed. The General-HL index was 37.22 (SD 7.98), which corresponds to sufficient or non-limited health literacy. The Big Five personality traits accounted for 32.2% of the variance in health literacy. Of the traits, Conscientiousness emerged as the strongest predictor (β = 0.31, medium effect), followed by Neuroticism (β = −0.21, small effect) and Openness to experience (β = 0.15, small effect). Sex was also a significant predictor of health literacy (β = 0.14, small effect). These results suggest that personality plays a significant role in health literacy, with higher Conscientiousness, lower Neuroticism, and higher Openness to experience, as well as female sex, predicting better health literacy. These findings underscore the importance of considering personality traits in interventions aimed at improving health literacy, with potential implications for both theoretical understanding and practical application in healthcare settings. Full article

Background: The use of pre-workout supplements has surged among fitness practitioners, with various ingredients purported to enhance performance and recovery. This study aims to explore the potential link between pre-workout supplement consumption and aggression, as well as the correlation between the Big Five personality traits and aggression levels. Methods: The sample comprised 62 male fitness practitioners aged 20–55 years, divided into two groups: 32 pre-workout consumers and 30 non-consumers. Participants were assessed using the Buss and Perry Aggression Questionnaire and the NEO Five-Factor Inventory (NEO-FFI). Results: The results indicated no statistically significant differences in aggression levels between the supplement users and the control group. However, notable personality differences were observed, with pre-workout users showing lower Neuroticism and higher Agreeableness and Conscientiousness compared to non-users. Correlation analyses revealed a significant positive relationship between Neuroticism and all forms of aggression, while Agreeableness and Conscientiousness were negatively correlated with aggression. Conclusions: These findings suggest that personality traits may play a more substantial role in moderating aggression among pre-workout users than the supplements themselves. Further research is needed to clarify the potential long-term effects of pre-workout supplementation on aggression and personality dynamics. Full article