Depression is a major public mental health problem worldwide, which impacts life with a high incidence and is among the greatest contributors to the global burden of diseases, including physical health and risk behaviors (Prince et al., 2007; James et al., 2018). According to the China Mental Health Survey, the lifetime prevalence and 12-month prevalence of depressive disorders in China were 6.8 and 3.6%, respectively (Huang et al., 2019). Since 2010, depressive disorders have been the second leading cause of years lived with disability, and people with depressive disorders have reported significant social impairment in China (Yang et al., 2013; Lu et al., 2021). Numerous factors are associated with depression, and the etiology is complex. The diathesis–stress theory of depression, proposed three decades ago by Monroe and Simons (1991), suggests that stress activates vulnerability, transforming a potential predisposition into psychopathology. The theory highlights the synergistic relationship between diathesis and stress.

Personality traits have been identified as diathesis factors for depression—high scores of neuroticism increase the risk of depression (Feizi et al., 2014; Nouri et al., 2019; Sheldon et al., 2021), whereas high extroversion has been considered a protective factor against stress response in mood disorders (Liu et al., 2022; Nin et al., 2023). López et al. (2017) found that the primary and overall personality dimensions explained 28% of the variance in depression. Studies indicated that vulnerable personality traits lead to the onset and development of depression through multiple pathways (Klein et al., 2011). In addition, another perspective suggested that the differences in depression cannot solely be attributed to personality traits (Milić et al., 2019).

According to the diathesis–stress theory, stress arises from life events that disrupt the psychological balance. Stress can catalyze the development of a disorder, and stressful life events (SLEs) are a predictor of susceptibility to subsequent depression (Tennant, 2002; Ngasa et al., 2017; Bjørndal et al., 2023; Crouse et al., 2024). The transactional theory of stress and coping indicates that individuals assess situations and adopt coping strategies, typically categorized as problem-focused, emotion-focused, or avoidant. Many studies suggested that coping strategies during stress mediate depressive symptoms. Active coping is associated with decreased depression levels, whereas frequent use of maladaptive strategies is related to increased depressive symptoms (Stikkelbroek et al., 2016; Kugbey et al., 2018; Pelekanakis et al., 2022; Alshowkan et al., 2023; Kumar et al., 2023). A dynamic precursor model suggested that depression and stress are mutually predictive factors. SLEs predict subsequent neuroticism at three out of four intervals (Goldstein et al., 2020). However, a recent study presented a different perspective, showing that the level of depression may be relatively high even if a moderate level of adaptability and active coping strategies are applied during stressful life events (Huang et al., 2022). Further discussion on the mutual relationship between SLEs, coping strategies, and depression remains urgently needed. Moreover, other factors related to personality traits and community networks, such as social support and utilization, physical activity, personal competence, and acceptance, are considered potential protective factors against depression (Choi et al., 2022; Ferber et al., 2022; Lu et al., 2023; Iovoli et al., 2024). The diathesis–stress theory of depression is illustrated in Figure 1.

Previous studies have focused on the individual effects of factors such as personality traits, life events, and social support. However, several other risk factors may exist simultaneously in actual situations. The combination of various features is complex and variable for individuals. In this study, we aimed to identify the different combinations of personality traits, SLEs, and coping strategies that have greater potential to cause depression among adult community residents.

The fuzzy-set qualitative comparative analysis (fs-QCA) is a research method that blends qualitative and quantitative approaches, combining fuzzy set theory and logic principles with QCA as proposed by Ragin (2000). fs-QCA has been widely used in public health studies in recent years (Breuer et al., 2018), including evaluations of public health interventions and discussions of the risk factors of occupational stress (Quan et al., 2022). In this study, we applied fs-QCA to analyze the effects of personality traits, SLEs, and coping styles during stress among adult community residents in Shenzhen, China and to identify high-risk factor sets for depression. This study aimed to provide a theoretical basis for effectively coping with depression and planning intervention measures.

From the sociological perspective, individuals exhibit a complex combination of characteristics. This study examined the combined relationship between depression, personality traits, and psychosocial stress using fs-QCA. We identified that the combination of low extroversion (e and high neuroticism (N) in personality traits with high life events (V), high negative emotional responses to events (G), high positive emotional responses to events (O), and high positive coping styles to events (I) constitutes a high-risk factor set for depression. However, this factor set represents sufficient but not the necessary conditions for depression, indicating that individuals with a combination of these factors are more likely to experience depression compared to others.

Many studies have discussed the relationship between personality traits and depression, and personality has been considered a key factor in depression. High-order personality factors, including neuroticism and extroversion, are significantly and consistently associated with depression (Grav et al., 2012). A study on a community-based lifespan sample in the United States demonstrated that high neuroticism and low extroversion were the most significant predictors of depression in a machine-learning model (Yang et al., 2024). Neuroticism, a partially heritable personality trait representing high emotionality and sensitivity (Matthews and Whiteman, 2009), maybe the strongest predictor of depression (Enns and Cox, 1997; Nouri et al., 2019; Crouse et al., 2024). Previous studies on personality traits and depression have overlooked the correlation between introversion and depression. However, research suggests a promising association between introversion and the outcomes of depression, with introversion potentially representing a heritable trait of etiologic significance (Janowsky, 2001). Introverts tend to report fewer pleasant experiences (DeMeo et al., 2023). Our analysis supports the idea that a combination of high neuroticism and low extroversion in personality dimensionality is a high-risk factor set for depression.

SLEs are consistently considered having significant association with depressive symptoms (Kessler, 1997; Kendler et al., 1999; Hammen, 2005; Stroud et al., 2008). A longitudinal study suggested a direct correlation between increased neuroticism, aggregation of SLEs, and more severe depressive symptoms. It demonstrated that negative life events partially mediate the relationship between neuroticism and depression (Zheng et al., 2024). Maladaptive coping strategies are associated with more depressive symptoms, whereas resilience and positive coping styles moderate the relationship between SLEs and depression (Stikkelbroek et al., 2016; Zhao et al., 2021; Huang et al., 2022). However, some studies suggested that, despite significant heterogeneity in how people respond to stress, SLEs and perceived stress are central risk factors in the complex depression network (Tennant, 2002; Ngasa et al., 2017; Goldstein et al., 2020; Bjørndal et al., 2023; Iovoli et al., 2024). Our study found that a high score in life events, combined with both positive and negative emotional responses and positive coping styles, constitute a high-risk factor set for depression. This finding is consistent with the result of a recent study showing that the level of depression is relatively high even if a moderate level of adaptability and positive coping strategies are adopted in stressful life environments (Huang et al., 2022). We suggest that stress plays an independent and significant role in depression, with stressors, along with personality predispositions, forming a risk set for depression.

This study has certain limitations. First, the fs-QCA method used is a qualitative analysis and does not explain the quantitative effect of variables. Second, due to the cross-sectional approach used in our study, the association between depression and personality and stress cannot be interpreted causally. Third, volunteer bias may occur due to the sampling process. The prevalence of depression in our study was 6.36%, higher than the 12-month prevalence of depressive disorders in the China Mental Health Survey (Huang et al., 2019), possibly indicating that individuals with depression were more likely to participate. Although their participation may increase the statistical power, it may not impact the magnitude of the observed associations.

Rather than limiting to single-factor effects, our study explored the combined high-risk factor sets of personality traits and psychological stress on depression in adult community residents using the fs-QCA method. The findings of the present study suggest that SLEs combined with personality traits, including neuroticism and introversion, serve as crucial factors in depression among adult community residents, regardless of whether they use positive or negative coping strategies. To reduce the prevalence of depression among adult community residents, comprehensive approaches that regulate the levels of neuroticism and introversion and actively integrate social resources to mitigate stressors should be adopted.

The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.

The studies involving humans were approved by Ethics Committee of Shenzhen Kangning Hospital. The studies were conducted in accordance with the local legislation and institutional requirements. The participants provided their written informed consent to participate in this study.

XY: Writing – original draft, Methodology. LY: Methodology, Writing – original draft. SZ: Project administration, Writing – review & editing. ZW: Project administration, Supervision, Writing – review & editing. GX: Methodology, Supervision, Writing – review & editing. JW: Funding acquisition, Resources, Supervision, Writing – review & editing.