Impact of academic stress on achievement among medical postgraduates: the moderating role of the Big Five personality traits

Abstract

Purpose

The study aims to examine how academic stress affects academic achievement among medical graduate students and to explore the moderating role of the Big Five personality traits in the relationship between academic stress and academic achievement.

Methods

A cross-sectional survey was conducted in December 2024 among 658 participants using an anonymous questionnaire that included three measurement scales (academic stress, academic achievement, and the Big Five personality) and general sociodemographic information. AMOS 26.0 was used to assess the scales' structural validity, and SPSS 26.0 was used to test for common-method bias, provide general descriptive statistics, and conduct correlation analyses. The PROCESS v4.1 macro was used to test for moderated effects.

Results

Academic stress negatively predicted academic achievement among medical graduate students (β = -0.544, p < 0.001), and the main effects of each factor of academic stress on academic achievement were significant (all p < 0.001). Openness in the Big Five personality played a crucial moderating role in the relationship between academic stress and academic achievement (β = -0.133, F = 144.641, p < 0.05), and it significantly moderated the relationship between each factor of academic stress and academic achievement.

Conclusion

The higher the academic stress levels, the lower the academic success of medical master's students; however, students with higher open-mindedness personality traits exhibit a weaker negative correlation between stress and academic achievement. This finding suggests that personality traits are a crucial factor closely linked to academic achievement and may play a positive role in stress coping processes, supported by the most extensive study of these relationships to date. It is advised that colleges and universities implement strategies to lower academic stress among medical master's students to improve their academic achievement.

Introduction

The Organization for Economic Co-operation and Development reports that students globally face stress from academic and social experiences, among other factors, as academic expectations rise [1]. The 2020 China College Student Health Survey Report revealed that over 60% of college students experienced academic stress in the past year, with students pursuing master's and doctoral degrees reporting particularly high levels of stress [2]. As a unique group of college students, medical students often encounter greater psychological and academic stress due to the social development and complexity of the medical environment [3]. Academic stress is considered the most significant psychological stressor for medical master's students [4] and has severely affected their normal academic progress.

Academic achievement refers to learning outcomes or learning effectiveness, primarily focusing on the results, gains, or states attained by learners during the learning period [5]. This topic has long been a key issue in educational psychology research, and there is no uniform standard for measuring the dimensions of academic achievement due to varying research perspectives and the complexity of the concept itself. The current classification of academic achievement dimensions encompasses multiple aspects, including cognitive, non-cognitive, socio-emotional, metacognitive, and others [6–8]. As an evaluation indicator of students' overall quality, academic achievement is closely linked to degree completion, competency enhancement, and learning satisfaction [9], reflecting the academic level of individual development among medical master's degree students. While many researchers in the existing literature have identified student motivation, cognitive ability, mental health level, family parenting style, teacher quality, and school resources as key factors influencing academic achievement [10, 11], few have directly recognized student academic stress as an influencing factor on academic achievement.

Regarding the definition of stress, Lazarus's stimulus-reflection theory is commonly used. Stress is a physical or mental event that occurs during an individual's interaction with the environment, triggered by the individual's cognitive assessment of the stimulus [12]. Academic stress, on the other hand, is defined as the application of stress in the context of student learning, specifically referring to the state of anxiety and helplessness students experience during the learning process due to the feeling that academic tasks are beyond their capabilities [13]. According to the school stress model [14], academic stress can be further subdivided into Social Relationships, Self-Development Stress, and Academic Demands. This multidimensional categorization not only helps comprehensively understand all aspects of the academic stressors faced by medical master's degree students but also provides a more nuanced perspective for further exploration of the relationship between academic stress and academic achievement. Some studies have shown that not all stressors inhibit performance [15, 16]. In other words, different types of academic stressors may have inconsistent effects on academic achievement.

Lazarus's stress model suggests that stress is neither inherent to individuals nor part of the environment; rather, it arises from an interaction between the individual and the environment [17]. The family and school, as the microsystems with which students have the most direct contact and as primary sources of social relationships, play a significant role in influencing the academic achievement of M.S. students. For example, the family environment has a considerable impact on students' academic achievement [18]. Adverse home environments may place greater stress on students' lives and learning. Additionally, a global survey of graduate students published in Nature found that interactions between supervisors and graduate students can significantly affect graduate students' psychological well-being and learning outcomes [19]. Strained mentor-student relationships are also a significant source of academic stress for graduate students [20]. Similarly, interpersonal conflicts in peer relationships not only lead to emotional depression and social anxiety but also cause students to experience greater academic stress and may hinder their development [21].

According to the Yerkes-Dodson law [22], a moderate level of self-stress can enhance motivation and academic achievement,however, when stress exceeds an individual's coping capacity, it can lead to poor academic achievement and mental health issues. A study conducted by scholars on graduate students from a top university in Beijing found that the primary source of psychological pressure they encounter is academic stress. The more dissatisfied graduate students feel with their academic achievements, the more negative emotions they associate with this stress [23]. In other words, the stress to develop oneself among graduate students also affects academic achievement. It has also been shown that excessive academic demands can lead to cognitive overload, inhibiting schema construction and transfer ability [24]. This overload renders students unable to process information effectively,as a result, their knowledge remains fragmented, making it difficult to transfer to new contexts. It even triggers psychological stress, which leads to anxiety, decreased motivation, and lower self-efficacy [25]. The impact of academic demands on academic stress is clear, and it has been proposed that excessive academic demands may lead to anxiety, cheating, or dropping out of school [26].

Moreover, academic stress is highly likely to cause physical and mental health issues [27]. Prolonged excessive academic stress diminishes graduate students' psychological resilience, weakens motivation, and fosters academic burnout [28–30], which may further lead to decreased academic efficiency, lower quality of decision-making, and hindered scientific innovation [23]. Ultimately, these factors inevitably impact graduate students' academic achievements.

The Big Five personality theory is a model that describes the five primary personality traits. These dimensions are independent of one another and relatively stable, allowing them to predict and explain individuals' behavioral and emotional responses across situations over time [31]. This theory serves as an important and widely applicable framework for personality traits, encompassing five elements: Extraversion, Neuroticism, Conscientiousness, Agreeableness, and Openness [32]. It is generally recognized that individuals differ in their ability to cope with stress. Individuals with a resilient personality tend to manage stress effectively and regulate their emotions well in high-intensity, stressful situations. Previous studies have shown that the Big Five personality traits partially mediate the link between work stress and work achievement [33], helping individuals cognitively process external environmental pressures and present themselves accordingly, thereby adjusting their attitudes and behaviors [34]. Research indicates that personality also influences students' perceived stress. Groups with high Big Five scores tend to proactively seek resources to reduce anxiety levels when facing academic stress [35]. This proactive coping strategy not only helps reduce current stress but may also boost academic achievement through positive behavioral approaches. Therefore, when predicting college students' academic achievement based on the five personality traits, the predictive power of different traits varies [36]. For example, individuals with high Neuroticism, due to their sensitive and anxious nature, often perceive higher stress levels [37], making them more prone to psychological distress and burnout [38], which can lead to lower academic achievement. Similarly, students with low Extraversion, low Openness, and low Conscientiousness may become trapped in an anxiety cycle due to excessive focus on negative evaluations, experiencing stronger subjective stress perception even at the same objective stress level, thereby affecting learning efficiency [39]. These findings suggest that personality traits are not merely 'filters' for stress but can also modify the causal pathway linking stress to academic outcomes through behavioral regulatory mechanisms.

Additionally, studies show inconsistent predictive effects of Extraversion, Agreeableness, Conscientiousness, and Openness on academic achievement. Some studies suggest that Extraversion may alleviate personal stress and enhance academic achievement by promoting social interaction and resource gathering, while others highlight the important role of Conscientiousness in academic persistence [40–42]. This discrepancy may result from moderating effects of sample characteristics or cultural backgrounds, so this paper focuses on medical master's students to analyze the dynamic relationship between personality traits and academic achievement.

In summary, medical graduate students, as a special group, face high academic demands, rigorous research training, and uncertainties in their future careers [29]. These factors collectively create a unique academic stress environment. Current chinese research primarily focuses on identifying stressors among medical graduate students, including academic, employment, and economic stress, as well as mental health issues [43]. International research has confirmed the link between personality traits and stress coping mechanisms [44]. However, it lacks a systematic exploration of the dynamic mechanisms of stress-personality-accomplishment in medical education, particularly in the context of the 'high-expectation culture' in Chinese medical education. This study develops a framework for analyzing the types of academic stress experienced by medical master's students and how various stress dimensions affect academic achievement. It seeks to reveal the moderating effects of the Big Five personality traits and, within a certain range, attempt to explore a stress buffering model applicable to the group of medical postgraduate students, providing a localized perspective for the paradox of 'high stress—low achievement', in order to assist medical colleges and universities in formulating a dual-track intervention strategy of 'stress management—personality cultivation'.

Therefore, this study employs a classification of academic stress [14] to examine how different types of academic stress affect academic achievement and the moderating influence of the Big Five personality traits on the relationships between academic stress and achievement, specifically among medical master's degree students. Accordingly, we propose the following hypotheses and the model framework (Fig. 1).

• H1: Academic stress directly impacts academic achievement among medical postgraduates.

• H1a: Professional study stress affects academic achievement.

• H1b: Scientific research stress affects academic achievement.

• H1c: Academic ecological stress affects academic achievement.

• H1d: Self-development and employment stress affects academic achievement.

• H2: The Big Five personality traits of medical postgraduates play a moderating role in the relationship between academic stress and academic achievement.

• H2a: Neuroticism moderates the relationship between academic stress and academic achievement.

• H2b: Conscientiousness moderates the relationship between academic stress and academic achievement.

• H2c: Agreeableness moderates the relationship between academic stress and academic achievement.

• H2d: Openness moderates the relationship between academic stress and academic achievement.

• H2e: Extraversion moderates the relationship between academic stress and academic achievement.

Fig. 1.

A Moderation Model among academic stress, academic achievement, and Big Five personality in medical postgraduates

Methods

Participants and process

The cross-sectional survey for this study was conducted from December 20, 2024, to January 5, 2025, at a medical university in eastern China, using a full-cluster sampling method. We used the medical master's training units within the university as the basic sampling units, with all colleges offering medical master's degree programs, such as the Clinical Medical College, Basic Medical College, and School of Public Health, as the primary cluster units. Within each college, we used grade level as the secondary cluster unit, ultimately taking the entire group of medical master's students in each grade as the sampling frame. By employing cluster sampling across all colleges, we achieved comprehensive coverage of the medical master's student population at the university, ensuring that the sample could represent the characteristics of graduate students from different professional backgrounds and training systems. The questionnaire was collected through the Questionnaire Star online platform (https://www.wjx.cn/), and all data were processed anonymously, without any personally identifiable information. To ensure the sample's appropriateness and representativeness, strict inclusion criteria were established for respondents: master's degree students enrolled in their first, second, or third year of study who provided informed consent and voluntarily participated in the study. Undergraduate and doctoral students, as well as those with withdrawal or suspension status, were excluded from the study.

In this study, G*Power 3.1 [45] was used to conduct pre-efficacy analyses. The core analyses involved moderated effects analyses of the Big Five personality traits. Main effects testing revealed a medium effect size (f² = 0.15, α = 0.05, and power = 0.80), using five new predictor variables and a total of 10 variables. A sample size of 92 was required. Interaction effects testing was set at a small effect size (f² = 0.04), employing Bonferroni's correction [46] with α = 0.01, power = 0.80, five new predictor variables, a total of 15 variables, and a required sample size of 455. Ultimately, 658 questionnaires were returned, indicating that the sample size was sufficient. After excluding outlier questionnaires and those with regular responses, 616 valid questionnaires were obtained, resulting in a validity rate of 93.62%. Basic information about the study subjects included their gender, grade level, and home location. Among them, there were 310 males and 306 females,301 held academic master's degrees, while 315 held professional master's degrees; 204 were first-year master's degree holders, 215 were second-year master's degree holders, and 197 were third-year master's degree holders; 336 were urban students, and 228 were rural students.

Research instruments

Academic stress questionnaire

To evaluate the academic stress levels of medical master's students, this study relies on the sources of academic stress proposed by Salmela-Aro and Upadyaya [14]. It modifies the psychological stress scale for postgraduates developed by Chen and Jian [47] and the Academic Expectations Stress Inventory (AESI) by Ang and Huan [48], tailored specifically for medical master's students. These scales measure different aspects of academic stress and have demonstrated good relevance in previous studies involving master's students in similar contexts. After testing for homogeneity, three items with CITC values below 0. 0.4 were eliminated. Following expert consultations, the final scale includes four dimensions and 22 items: professional study stress (e.g., "I have many professional courses and demanding learning tasks"), scientific research stress (e.g., "I feel very distressed when writing academic papers or conducting experiments"), academic ecological stress (e.g., "I feel pressured by high expectations from my parents regarding my studies"), and self-development and employment stress (e.g., "I feel stressed about learning due to the large number of graduates and the competitive job market"). Items 1–4 of the professional study stress dimension, items 5–11 of the scientific research stress dimension, and items 18–21 of the self-development and employment stress dimension are adapted from the Psychological Stress Scale for Postgraduates. Items 12–17 of the academic ecological stress dimension are adapted from the ASQ scale. The scale employs a five-point Likert format. In this study, the Cronbach's alpha coefficients are: 0.898 for the learning task stress dimension, 0.930 for the research stress dimension, 0.920 for the interpersonal environment stress dimension, and 0.917 for the employment prospects stress dimension, with a total scale alpha of 0.933. Confirmatory factor analysis indicates a χ²/df value of 1.121, an RMSEA of 0.014, and GFI, NFI, IFI, and CFI values of 0.970, 0.978, 0.998, and 0.998, respectively, demonstrating excellent structural validity of the academic stress scale in this study.

Academic achievement

We used the Academic Achievement Scale developed by Chinese scholars [49], selecting three subscales—academic dedication, interpersonal facilitation, and academic performance—as the academic achievement questionnaire for medical master's degree students, comprising 16 items in total. The scale utilized a five-point Likert scale. In this study, the academic dedication subscale consisted of five items, including “I will work overtime to complete my study and research tasks on time,” with a Cronbach’s alpha coefficient of 0.918. The interpersonal facilitation subscale consisted of six items, including “I am very motivated to participate in the division's activities,” with a Cronbach’s alpha coefficient of 0.923. The academic performance subscale consisted of five items, for example, “I am able to achieve the expected goals in my studies/research,” with a Cronbach’s alpha coefficient of 0.923. The total scale’s Cronbach’s alpha coefficient in this study is 0.922, indicating a firm internal consistency and high reliability. The scale validation factor analysis revealed that χ²/df was 1.628, the RMSEA was 0.032, and the results for GFI, NFI, IFI, and CFI were 0.968, 0.977, 0.991, and 0.991, respectively, indicating that the structural validity of the academic achievement scale in this study was excellent.

Big Five inventory

Given the length of the research questionnaire and respondents' psychological fatigue, while ensuring scientific reliability, this paper uses the Chinese version of the Big Five Personality Inventory in Brief (CBF-PI-B) developed by Wang, Dai, and Yao [49, 50]. The scale consists of five dimensions: Neuroticism, Conscientiousness, Agreeableness, Openness, and Extraversion. Each dimension contains 8 items, for a total of 40. The scale uses a five-point Likert scale, with the following items reverse-scored: 5, 8, 13, 15, 18, 32, and 36. In this study, the Cronbach's α coefficient of the scale was 0.951, indicating firm internal consistency and high reliability. Validated factor analysis showed that the χ²/df was 1.057, the RMSEA was 0.01, and the results for GFI, NFI, IFI, and CFI were 0.941, 0.950, 0.997, and 0.997, respectively, indicating superior structural validity of the Big Five Personality Scale in the present study.

Data statistics

SPSS 26.0 was used to conduct common method bias (CMB) tests, perform general descriptive statistics, and analyze correlations. We employed the Unified Linear Model with Control (ULMC) to test for common method bias [51]. A VIF ≤ 10 indicates the absence of severe multicollinearity [52]. Validated factor analysis of the scales was conducted using AMOS 26.0. According to the goodness-of-fit criterion, χ²/df < 5 represents acceptable validity, while < 3 signifies good validity [53], RESEA ≤ 0.08 suggests acceptable validity, with the ideal condition being RESEA ≤ 0.06; and CFI ≥ 0.95 indicates good structural validity [54]. Moderated effects tests were performed using Model 1 in the PROCESS 4.1 macro [55].

Ethical approval

The survey adhered to the Helsinki Declaration and received approval from the Ethics Committee of Xuzhou Medical University (approval number: XZHMU-2024S071). Prior to data collection, participants were informed that their data would be used solely for research purposes and that the questionnaire would be anonymous and self-reported. The principles of privacy protection and confidentiality were maintained, ensuring that participants clearly understood the purpose, methodology, potential risks, and benefits of this study. Informed consent was obtained via digital signature, and all participants were informed of the complete voluntariness of their participation. Participation in the investigation is optional, and participants can withdraw at any point.

Results

Unified linear model with control and diagnosis of multicollinearity

Using ULMC for statistical analysis, a four-factor baseline model χ²(183) = 205.189 was developed. Then, a common method factor was added to the baseline model, constraining all item loadings to be equal, creating a complete model (χ²(182) = 196.300). The chi-square difference test showed that the complete model fit better than the baseline model (Δχ²(1) = 8.889, p < 0.01), indicating the presence of common method bias in the data. To evaluate its severity, we calculated the proportion of variance explained by the method factor in the complete model. The results revealed that the average variance explained by the method factor for each item was 14.00%, which is below the critical standard of 25%. Moreover, after accounting for the method factor, the factor loadings of professional study stress, scientific research stress, academic ecological stress, and self-development and employment stress on their respective items remained high and statistically significant, preserving the scale's structural validity. Thus, the extent of common method bias in this study is not significant enough to threaten the validity of the results and conclusions. The results of the multicollinearity diagnosis indicate that the VIF values for all items are below 3, well below the critical threshold of 10. The tolerance is greater than 0.1, indicating no multicollinearity issues.

Descriptive statistics and Pearson correlation analysis

Table 1 presents the mean values and Pearson correlation coefficients of the variables. The Pearson correlation analysis revealed a significant negative correlation between academic stress and overall academic achievement. Among these variables, a notable positive correlation was identified between professional study stress and academic achievement. Conversely, significant negative correlations were observed among scientific research stress, self-development, employment stress, academic ecological stress, and academic achievement. Regarding the relationship between different types of Big Five personality traits and academic achievement, we found that Neuroticism was significantly negatively associated with academic achievement. Meanwhile, Conscientiousness, Agreeableness, and Openness exhibited significant positive relationships with academic achievement. Concerning the relationship between academic stress and the Big Five personality traits, we found that Neuroticism demonstrated a substantial positive correlation with overall academic stress (p < 0.01). Conscientiousness, Agreeableness, Openness, and Extraversion all showed significant negative correlations with academic stress (all p < 0.01).

Table 1.

Analysis of the correlation between academic stress, Big Five personality, and academic achievement

Variable	M ± SD	1	2	3	4	5	6	7	8	9	10	11
1. Academic stress	3.17 ± 0.61	1
2. PSS	2.75 ± 1.28	−0.091*	1
3. SRS	3.35 ± 1.17	0.691**	−0.410**	1
4.AES	3.31 ± 1.14	0.709**	−0.433**	0.463**	1
5.SAES	3.28 ± 1.31	0.732**	−0.402**	0.411**	0.459**	1
6. Academic achievement	2.76 ± 0.96	−0.544**	0.521**	−0.559**	−0.546**	−0.556**	1
7. Neuroticism	3.20 ± 1.01	0.418**	−0.437**	0.439**	0.434**	0.442**	−0.514	1
8. Conscientiousness	2.79 ± 1.03	−0.405**	0.475**	−0.443**	−0.456**	−0.431**	0.562**	−0.402**	1
9. Agreeableness	2.80 ± 1.01	−0.400**	0.433**	−0.443**	−0.430**	−0.402**	0.544**	−0.419**	0.442**	1
10. Openness	2.75 ± 0.98	−0.387**	0.409**	−0.427**	−0.421**	−0.378**	0.520**	−0.401**	0.441**	0.461**	1
11. Extraversion	2.77 ± 1.04	−0.403**	0.445**	−0.432**	−0.429**	−0.432**	0.583**	−0.390**	0.444**	0.431**	0.434**	1

PSS Professional study stress, SRS Scientific research stress, AES Academic ecological stress, EPS Self-development and employment stress

^*p < 0.05

^**p < 0.01

Analysis of direct and moderating effects of academic stress on academic achievement

Table 2 shows that academic stress is significantly negatively correlated with academic success among medical master's students (β = −0.544, p < 0.001). H1 is supported. Moreover, Neuroticism (β = −0.645, p < 0.001), Conscientiousness (β = 0.640, p < 0.001), Agreeableness (β = 0.505, p < 0.001), Openness (β = 0.771, p < 0.001), and Extraversion (β = 0.571, p < 0.001) were identified as significant predictors of academic achievement. H1a, H1b, H1c, and H1d are likewise supported. However, the interaction terms between Neuroticism, Conscientiousness, Agreeableness, and Extraversion with academic stress were not significant (p > 0.05), indicating that these traits did not significantly moderate the relationship between academic stress and academic achievement. In addition, the interaction term between Openness and academic stress was significant (β = −0.133, p < 0.05) and had a 95% confidence interval of [−0.24, −0.03]. These results suggest that Openness significantly moderates the relationship between academic stress and academic achievement. Only H2d is valid.

Table 2.

The direct effect and the moderating effect on academic achievement

Variable	Baseline model	Model 1	Model 2	Model 3	Model 4	Model 5
Academic stress	−0.544***	−0.935***	−0.351*	−0.481***	−0.242	−0.420**
Neuroticism		−0.645***
Academic stress × Neuroticism		0.101
Conscientiousness			0.640***
Academic stress × Conscientiousness			−0.083
Agreeableness				0.505**
Academic stress × Agreeableness				−0.043
Openness					0.771***
Academic stress × Openness					−0.133*
Extraversion						0.571***
Academic stress × Extraversion						−0.054
R2	0.296	0.399	0.438	0.424	0.415	0.455
△R2	-	0.103	0.142	0.128	0.119	0.159
F	258.480***	135.465***	159.209***	149.924***	144.641***	170.178***

^*p < 0.05

^**p < 0.01

^***p < 0.001

To better reflect the regulatory mechanism of Openness, a schematic diagram illustrating the moderating effect is presented (Fig. 2). It shows that, under similar stress conditions, the academic achievement of postgraduates with high Openness is higher than that of students with low Openness. Additionally, when the Openness trait shifts from a low level to a high level, the slope of the effect of the independent variable (academic stress) on the dependent variable (academic achievement) decreases from −0.485 to −0.688. This indicates that as Openness increases, the negative impact of academic stress on achievement weakens.

Fig. 2.

Simple slope plot of academic stress on academic achievement, with openness as a moderator

Analysis of the direct and moderating effects of academic stress dimensions on academic achievement

Openness was used as a moderator to examine its effect on the relationship between various types of academic stress and academic achievement. The results (Table 3) indicated that among the dimensions of academic stress, professional study stress significantly and positively predicted academic achievement (β = 0.216, p < 0.001). In contrast, scientific research stress (β = −0.265, p < 0.001), academic ecological stress (β = −0.208, p < 0.001), and self-development and employment stress (β = −0.265, p < 0.001) all exerted significant negative predictive effects on academic achievement. Hypotheses H1a, H1b, H1c, and H1d were all supported. Additionally, the Openness trait was associated with professional study stress (β = 0.065, p = 0.013, 95%CI [0.01, 0.12]), scientific research stress (β = −0.062, p = 0.030, 95%CI [−0.12, −0.01]), academic ecological stress (β = −0.107, p = 0.002, 95%CI [−0.16, −0.05]), and self-development and employment stress (β = −0.091, p = 0.002, 95%CI [−0.14, −0.04]), indicating significant interaction terms. This suggests that the Openness personality trait moderates the relationship between different types of academic stress and academic achievement.

Table 3.

The moderating effect of Openness between each dimension of academic stress and academic achievement

	Baseline model		Model 6			Model 7			Model 8			Model 9
	β	p	β	p	95%CI	β	p	95%CI	β	p	95%CI	β	p	95%CI
PSS	0.216	< 0.001	0.100	0.193	[−0.05,0.25]
SRS	−0.265	< 0.001				−0.167	0.057	[−0.34, 0.01]
AES	−0.208	< 0.001							−0.026	0.760	[−0.19, 0.14]
EPS	−0.265	< 0.001										−0.057	0.428	[−0.20, 0.08]
Openness (W)			0.175	0.034	[0.01,0.34]	0.533	< 0.001	[0.34, 0.72]	0.692	0.000	[0.50, 0.88]	0.636	< 0.001	[0.48, 0.80]
PSS × W			0.065	0.013	[0.01,0.12]
SRS × W						−0.062	0.030	[−0.12, −0.01]
AES × W									−0.107	0.002	[−0.16, −0.05]
EPS × W												−0.091	0.002	[−0.14, −0.04]
R2	0.522		0.391			0.414			0.414			0.435
F	166.761 (p < 0.001)		131.062 (p < 0.001)			143.829 (p < 0.001)			144.274 (p < 0.001)			156.750 (p < 0.001)

PSS Professional study stress, SRS Scientific research stress, AES Academic ecological stress, EPS Self-development and employment stress

The simple slope plots of the moderating effect (Fig. 3) indicated that individuals with high Openness traits are more likely to achieve higher academic achievement in the professional study stress dimension. Specifically, as Openness increases from low to high levels, the strength of the association between academic stress and academic achievement also grows, rising from 0.215 to 0.342, indicating a positive moderating effect of Openness on the relationship between the two variables. This suggests that as Openness traits increase, the positive correlation between academic stress and academic achievement becomes stronger.

Fig. 3.

Simple slope plot of different academic stresses on academic achievement, with openness as a moderator

However, across dimensions such as scientific research stress, academic ecological stress, and self-development and employment stress, the negative correlation between stress and academic achievement gradually weakened as openness levels increased. This moderation pattern indicates that the openness trait exerts a negative moderating effect on the relationship between various negative academic stressors and academic achievement variables. From the perspective of the Conservation of Resources theory, individuals with high Openness actively seek to integrate knowledge and use diverse cognitive strategies to build a psychological resource pool, thereby creating a pressure-buffering mechanism. Therefore, Openness negatively moderates the relationship between these pressure dimensions and academic achievement.

Discussion

This study comprehensively examines the correlation between academic stress and academic achievement among medical graduate students, as well as the moderating role of the Big Five personality traits. It further examined the moderating effect of Openness on the relationship between different types of academic stress and academic achievement, highlighting the significant role of personality traits in managing stress and achieving academic success. Research findings indicate that different types of academic stress significantly predict academic achievement among medical graduate students, while the Big Five personality traits partially mediate the relationship between academic stress and academic achievement. The Openness trait within the Big Five personality has a significant moderating effect on the relationship between different types of academic stress and academic achievement, reflecting the dual attributes of academic stressors and the enthusiasm associated with Openness.

Effects of academic stress on academic achievement

Firstly, this study found a significant negative correlation between academic stress and the academic achievement of medical postgraduates. An increase in academic stress over time will lead to a decline in students’ academic achievement. This finding is consistent with the results of many studies [18, 27, 56, 57]. This is primarily due to the long-term academic stress experienced by medical postgraduates, which can lead to adverse psychological and physiological effects [58] and subsequently result in declines in personal academic achievement and even professional consequences [38].

Secondly, by analyzing the relationship between different types of academic stress and academic achievement, we found that the stress experienced by medical master's students exhibits both positive and negative correlations with academic achievement, presenting a dual pattern. This relationship resembles a double-edged sword, with its specific direction and intensity varying depending on the type of stress and the coping strategies employed by medical master's students. According to the findings of this study, scientific research stress, academic ecological stress, and self-development and employment stress were significantly negatively correlated with academic achievement. In contrast, professional study stress showed a relatively stable positive correlation with academic achievement.

According to the ‘challenging-blocking’ pressure binary structure theory and the classification of pressure source attributes [59, 60], the professional study stress discussed in this paper serves as a beneficial pressure source, predominantly enhancing the learning enthusiasm of graduate students in the form of ‘challenging’ stress. Studies have shown that benign academic stressors can stimulate a sense of urgency [61], prompting medical graduate students to optimize time management and enhance their thesis writing abilities or experimental efficiency in the short term. Therefore, moderate stress can enhance the psychological resilience of medical students, making them more adaptable in the medical field in the future, while also improving their ability to integrate resources and multitask among medical postgraduates.

Contrary to the professional study stress, this study reveals that the scientific research stress among medical postgraduates may hurt academic achievement. Scientific research stress primarily inhibits graduate students’ enthusiasm through a form of ‘blocking’ pressure, weakening their academic motivation and undermining scientific research output, ultimately leading to lower academic achievement among medical graduate students [62]. Furthermore, some scholars have examined the impact of pressure to publish in international academic journals on both the quantity and quality of scientific research publications. They also found that scientific research stress is detrimental to research publication, particularly when it stems from a ‘survival orientation,’ which negatively affects the production of high-quality academic papers [63]. Therefore, individuals who have experienced long-term pressure from scientific research may have a more difficult time achieving higher academic success, leading to distractions, decreased innovation, and lower-quality scientific research outcomes.

In addition, the study found that academic ecological stress exerts a significant negative predictive effect on the academic achievement of medical master's students, primarily in the form of ‘blocking’ pressure. According to the theory of ecosystem development, the academic ecological environment, consisting of parents, tutors, and classmates, represents the microsystem most directly encountered by medical graduate students. The stronger the personal correlation of stressors, the more likely individuals are to be negatively affected by them [64]. Influenced by traditional cultural concepts and the higher academic requirements and standards imposed on postgraduate students in colleges and universities, current medical postgraduates generally experience high academic stress [65]. Studies have shown that excessive external environmental pressure can easily contribute to students' depression, anxiety, and other emotional issues [66]. This stressor may impact the learning process of medical postgraduates through psychological, behavioral, and social pathways, leading to excessive expectations, anxiety, academic dependence, and inhibition of innovation, as well as ‘involution’ competition [67–69].

Finally, the present study demonstrated that self-development and employment stress experienced by master's students in medicine are negatively correlated with their academic achievement, consistent with the definition of “impeding stress” in stress theory. Previous research has suggested that career stress among medical students significantly affects academic engagement and psychological well-being, leading to fluctuations in academic achievement and increased anxiety [70]. According to Attention-Control Theory, anxiety makes individuals more susceptible to external distractions, which in turn causes them to consume excessive cognitive resources to maintain attention and resist task-irrelevant stimuli [71]. Meanwhile, the cognitive resource allocation theory further suggests that individuals reallocate cognitive resources under stress [72]. Therefore, persistent worry about their own development and employment prospects will consume the cognitive resources that medical master's degree students use for research or study, ultimately reducing study time and lowering academic achievement.

In summary, schools and medical units at all levels should establish a comprehensive support system that includes stress prevention, identification, intervention, and transformation to promote the sustainable development of medical talent. In managing student stress, educational interventions can focus on different types of stress to tailor strategies, refine existing general stress guidance approaches, promote ‘challenging stress’ positively correlated with academic achievement, and reduce ‘impeding stress’ negatively correlated with academic achievement. This may help improve the academic achievement of medical graduate students.

Role of Big Five personality

In this study, we found a significant association between the Big Five personality traits and academic achievement. This effect arises because personality influences a person's behavioral characteristics [73]. Specifically, a neurotic personality is characterized by negative emotional responses to stimuli, indicating lower emotional stability [74]. A longitudinal study reported that Neuroticism was the strongest contributor to psychological distress among medical students during stressful periods, such as final exams [75]. The literature indicates that medical students with certain personality traits, particularly Neuroticism, are more likely to experience psychological distress and burnout [76], while these factors are closely associated with declining academic achievement. In contrast, higher levels of Conscientiousness, Agreeableness, Openness, and Extraversion typically reflect positive emotional responses to stimuli. A meta-analysis found that Conscientiousness, which implies being organized, persistent, and responsible, had the strongest and most consistent association with academic achievement [77]. Students with high Agreeableness tend to be generally flexible, cooperative, tolerant, caring, trusting, supportive, altruistic, and amiable. On the other hand, high Openness indicates open-mindedness, a variety of hobbies, a willingness to embrace new experiences, and a richness in imagination and creativity [78]. All of these positive traits help medical graduate students maintain a constructive mindset and a strong internal drive to enhance their academic achievement. Individuals high in Extraversion typically exhibit traits such as energy, enthusiasm, gregariousness, sociability, confidence, and positive emotions [79]. Research has shown that individuals high in Extraversion are more inclined to communicate with and seek support from others within their team and organization [80], suggesting that extroverted medical graduates are often better positioned to share their creativity and access supportive learning resources, thereby achieving higher levels of academic success.

The study also revealed that the Big Five personality traits partially moderate the relationship between academic stress and academic achievement among medical master's students. Specifically, Openness negatively moderates the relationship between academic stress and academic achievement. Since academic stress is negatively correlated with academic achievement, meaning that increased stress levels may coincide with declining grades, while Openness to experience exerts a significant negative moderating effect on this relationship. Thus, higher levels of Openness weaken the negative association between academic stress and academic achievement. For example, at low levels of Openness, a one-unit rise in academic stress results in an average drop of 0.688 units in achievement; at high levels of Openness, the same increase in stress causes only a 0.485-unit decrease. This supports the idea that Openness functions as a moderating variable. Consequently, students with lower Openness are less likely to achieve higher academic success compared to those with higher Openness. Medical master's students with high Openness tend to be cognitively active, emotionally rich, and more willing to share ideas and engage in interactions during their learning and daily lives [81]. According to the demand-resource model, students with high Openness are better at transforming stress into growth opportunities and adjusting coping strategies flexibly during interactions with their environment, leveraging resources to boost academic achievement [82]. Furthermore, high Openness is often associated with lower interpersonal sensitivity, and some aspects of interpersonal sensitivity closely relate to depression, which significantly affects depression among Chinese graduate students [83]. Additionally, Bandura's social cognitive theory of learning suggests that human behavior results from dynamic interactions between the individual, behavior, and environment, with certain key aspects of personality influenced by environmental and behavioral feedback [34]. Thus, medical master's students with high levels of Openness have unique buffering advantages when facing academic stress: individuals with high Openness traits can reinterpret stressful situations through advanced cognitive abilities such as conceptual restructuring and cross-disciplinary linking [84]. This helps them counteract the negative effects of academic stress more effectively. Additionally, by actively leveraging strengths in their environment and combining experiences to develop personalized coping strategies, this type of environmental interaction, driven by these characteristics, significantly mitigates the negative correlation between academic stress and academic achievement. Therefore, a crucial psychological resource buffering mechanism is established in the stress-achievement pathway.

This moderating effect was not observed for the other five personality traits, except for Openness, suggesting that the other traits operate through different mechanisms. For Conscientiousness, its core lies in effort, organization, and responsibility [85]. Individuals with high Conscientiousness may not reduce stress by regulating its negative effects, but instead by using proactive, problem-focused coping strategies to directly reduce the occurrence or severity of stressors. In other words, the influence of Conscientiousness may manifest earlier in the stress process, rather than by buffering between stress perception and achievement. Additionally, in the high-stress environment of medical graduate studies, excessive self-monitoring among highly conscientious individuals may lead to a 'perfectionism anxiety cycle,' causing resource consumption to outpace replenishment, and thus failing to develop an effective regulatory mechanism.

For Extraversion and Openness, the core involves primarily acquiring social support and interpersonal resources. In the resource-competitive environment of medical research, the 'externally oriented' cognitive trait of highly extraverted and agreeable individuals may weaken their sensitivity to academic stressors, delaying alignment of stress perception with coping strategies, which may explain why their regulatory effects were not observed.

Moreover, this study further explored the moderating effect of openness between different levels of academic pressure and academic achievements. The results show that Openness personality exerts both positive and negative moderating effects in different academic pressure scenarios. This finding emphasizes the unique value of the Openness personality in how medical graduate students cope with academic stress.

Research findings indicate that Openness positively moderates the relationship between challenging academic stress (such as professional study stress) and academic success. Furthermore, this study reveals a positive correlation between professional study stress and academic achievement. This finding suggests that, within reasonable limits, maintaining an appropriate level of stress may positively influence the academic achievements of medical graduate students. Thus, the positive moderating effect of openness amplifies the beneficial relationship between professional learning stress and academic success. Conversely, Openness negatively moderates the relationship between impending academic stress—including scientific research stress, academic ecological stress, and self-development and employment stress—and academic achievement. Data indicate that these pressure types negatively predict academic achievement, while higher Openness levels weaken this negative association. This pattern suggests that Openness buffers the negative relationship between impending pressures and academic achievement.

Notably, although various types of academic stress directly predict academic achievement, none of the academic stress dimensions emerge as significant predictors when evaluated through the moderating model. This phenomenon can be attributed to interaction effects, whereby the direction or strength of the relationship between the independent and dependent variables may vary across levels of the moderator variable, thereby neutralizing the main effect. Moreover, these findings emphasize the significant moderating influence of Openness. Individuals with higher Openness scores are generally more adaptable in their behaviors and more driven to engage in intellectual activities, which broadens their knowledge base. Furthermore, Openness is thought to enhance knowledge accumulation and judgment substantially [86, 87]. Thus, motivated medical postgraduates can sustain a robust internal drive under demanding pressures, leading to greater academic accomplishments. Research also indicates that individuals who maintain an open mindset and continually seek new information and experiences are more likely to refine and update their foundational knowledge and insights about academic life [88]. This, in turn, reduces academic stress and promotes greater student dedication to their studies in an optimal state. Additionally, this study's comprehensive investigation of academic stress and achievement extends the application of social cognitive learning theory among graduate medical students.

Limitations and future research

This study has several limitations. First, this study employed a cross-sectional design, with all data collected at a single point in time. Consequently, this design cannot establish causal relationships among personality traits, academic stress, and academic achievement. Future research may use longitudinal tracking designs or experimental studies to further validate the directionality and causal relationships among variables.

Second, while this study captures the unique dynamics of the “stress-personality-achievement” mechanism among medical students, it does not categorize participants by specific medical specialties. This limitation may introduce bias when generalizing findings to particular medical fields. Future research should refine sample categorization and conduct in-depth analyses for students in different medical specialties to enhance the universality and specificity of research conclusions.

Third, because all data in this study are self-reported, this may introduce bias. Future research could establish a cohort to track the causal relationships among these variables. Additionally, incorporating multidimensional perspectives, such as evaluations from tutors, parents, and peers, could help reveal the sources of pressure affecting the academic achievement of medical postgraduates from various angles, thereby improving the robustness of the research findings.

Conclusion

This study provides empirical evidence on the relationships between academic stress, academic achievement, and the Big Five personality traits among medical postgraduates in China. Our results show that academic stress negatively predicts academic achievement, though some benign stressors still promote academic achievement. The Big Five personality traits significantly predict academic achievement, with Conscientiousness, Agreeableness, Extraversion, and Openness being the most relevant. Furthermore, the Big Five traits partially moderate the stress-achievement relationship; specifically, the Openness trait significantly moderated the relationship between academic stress and academic achievement among medical master's students, weakening the negative association between the two. This finding offers new insights into the role of personality in medical talent development. We recommend that universities and hospitals design personalized training programs for medical postgraduates, optimize learning and living environments, reduce course and practical workloads, and enhance overall outcomes. Additionally, fostering Openness among medical postgraduates and building positive psychological resources are crucial to maintaining their healthy learning and living.

Abbreviations

AES

Academic ecological stress

CFI

Comparative Fit Index

CITC

Corrected Item-Total Correlation

EPS

Self-development and employment stress

GFI

Goodness-of-Fit Index

IFI

Incremental Fit Index

NFI

Normed Fit Index

PSS

Professional study stress

RMSEA

Root Mean Square Error of Approximation

SRS

Scientific research stress

ULMC

Unified Linear Model with Control

VIF

Variance Inflation Factor

Authors’ contributions

HX conceived the study, supervised the process, and performed the analysis. HL and RG designed and conducted the literature search strategy, interpreted the data, and drafted the manuscripts. HX & RG built the data and performed the data analysis. All authors contributed extensively to this work, writing and reviewing the manuscript, and approved the final version.

Funding

This study is supported by Jiangsu Provincial University's Philosophy and Social Sciences Foundation Project (2021SJA1073) and the Special Commissioned Project on Student Financial Aid under the Jiangsu Province Education Plan (X-A/2023/08).

Data availability

The data used in this study are available on request from the corresponding author.

Declarations

Ethics approval and consent to participate

Research was conducted in accordance with the Declaration of Helsinki guidelines and was approved by the Ethics Committee of Xuzhou Medical University (approval number: XZHMU-2024S071). Informed consent was obtained from all individual participants included in the study.

Consent for publication

Not applicable.

Competing interests

The authors declare no competing interests.