Research has identified several psychological and social factors that consistently predict university adjustment outcomes. Among protective factors, sense of belonging has received robust empirical support. Students who feel connected and valued on campus report lower psychological distress and better academic outcomes (van Kessel et al., 2025). Psychological resilience is equally well-established. Higher academic resilience is positively associated with student well-being and engagement (Bagdžiūnienė et al., 2025). Identity development also shapes adjustment. Students who form clear identity commitments show better adjustment outcomes during university transition. Those who remain in ruminative exploration show poorer psychological adjustment (Luyckx et al., 2008).

Among risk factors, neuroticism is the most consistently implicated personality trait. It predicts emotional reactivity, stress sensitivity, and vulnerability to anxiety and depression (Luo et al., 2023). Extraversion, by contrast, is associated with better social integration and more proactive coping (Costa & McCrae, 1992).

Despite this body of evidence, an important gap remains. Most studies have been conducted in Western university populations. Whether these patterns hold for Chinese university freshmen remains unclear. Cultural values and institutional structures differ substantially (Markus & Kitayama, 1991; Xu, 2021). Culturally situated evidence is needed.

Five psychological conditions are examined in the present study. Self-identity exploration refers to the active investigation of one’s values, beliefs, and future directions. It is a central developmental task of early adulthood. Students who engage in active exploration and form clear commitments show better adjustment outcomes (Luyckx et al., 2008). Sense of belonging refers to the perceived connectedness to one’s university community. It is consistently associated with positive adjustment and reduced distress (van Kessel et al., 2025). Psychological resilience is the capacity to recover from adversity under stress. It is widely recognized as a key protective resource during major life transitions (Bagdžiūnienė et al., 2025). At the personality level, neuroticism is associated with emotional reactivity and stress vulnerability (Luo et al., 2023). Extraversion, in contrast, facilitates new social connections and active environmental engagement (Costa & McCrae, 1992). Emotional processes such as anxiety and disengagement have similarly been shown to shape learners’ psychological outcomes in educational contexts (Wang, 2026).

However, two gaps remain. First, most studies examine these factors independently using regression or structural equation modeling. These methods assume variables operate in isolation and cannot capture how conditions combine to produce an outcome. Yet adjustment difficulties rarely stem from a single factor. They emerge from specific configurations of co-occurring conditions. Second, the field has focused mainly on risk factors for maladjustment. Far less attention has been paid to combinations that protect against adjustment difficulties. Both risk and protective profiles are needed for effective and targeted intervention (Kahn, 2016).

Theoretical basis. Conservation of Resources Theory (Hobfoll, 1989) provides the theoretical foundation. COR Theory proposes that stress arises when individuals lack the resources needed to meet environmental demands. Within this framework, sense of belonging constitutes a condition resource. It provides relational security and institutional anchorage during the university transition. Self-identity exploration and psychological resilience both constitute personal characteristic resources. Self-identity exploration directs goal pursuit and motivates adaptive behavior in unfamiliar environments. Psychological resilience enables sustained coping under adversity and supports resource recovery. Neuroticism and extraversion, as personality characteristics, shape the rate at which these resources are acquired, depleted, and replenished. When multiple resources are absent simultaneously, adjustment difficulties increase. When resources co-occur in sufficient combinations, they buffer against maladjustment.

Chinese university freshmen are a psychologically vulnerable group. For most, university entry marks the first time living away from home. They must simultaneously adapt to new academic demands, rebuild social networks, and navigate identity changes. First-year undergraduates are particularly vulnerable to these multidimensional stressors (Liu et al., 2023). A systematic review and meta-analysis of 113 studies involving 185,787 Chinese university students found an overall depression prevalence of 28.4% (Gao et al., 2020). A recent national survey of 49,717 students from 106 Chinese universities further reported anxiety and depression detection rates of 15.5% and 9.8%, respectively (Han et al., 2025). In response, China’s Ministry of Education and sixteen other departments jointly issued a national action plan in 2023 to strengthen mental health services in higher education (Yuan et al., 2024).

This study utilized a two-stage analytical approach to examine the relative importance of conditions associated with university adjustment difficulties.

Two research questions guided the study:

RQ1: Which psychological characteristics are associated with college entry adjustment difficulties among university freshmen?

RQ2: What is the relative weighting of psychological characteristics in college entry adjustment difficulties?

To address these questions, two analytical methods were used. First, Necessary Condition Analysis (NCA) examined whether any single psychological characteristic is individually necessary for adjustment difficulties. Second, fuzzy-set Qualitative Comparative Analysis (fsQCA) identified sufficient combinations of conditions that produce high or low adjustment difficulties. Together, these methods advance understanding of how psychological resource configurations shape university adjustment among Chinese freshmen.

A total of 356 Chinese college students (females = 50.6%; age range 18 to 20 years, M = 19.01, SD = 0.80) were participants. In terms of age distribution, 31.5% were 18 years old, 36.5% were 19 years old, and 32.0% were 20 years old. Regarding home location, the majority of participants came from urban areas (60.7%), with the remaining 39.3% from rural areas. The data were obtained from a publicly available dataset (https://doi.org/10.57760/sciencedb.35811). Since this study was based solely on secondary analysis of anonymized and publicly accessible data, no additional ethical approval was required. Detailed demographic characteristics are presented in Table 1.

All scales were adapted from established instruments with demonstrated reliability and validity in Chinese student populations. Table 2 presents the number of items per scale.

Self-Identity Exploration (SIE). Self-identity exploration was assessed using the 10-item Ego-Identity Status Scale, revised for Chinese populations by Zhang (2000). The scale covers three dimensions: current self-investment (3 items; e.g., “I know what kind of person I am and what I hope to pursue”) past crisis experience (3 items; e.g., “I have seriously reflected on what kind of person I am and what I should do”), and aspiration for future self-investment (4 items; e.g., “I am actively exploring things I can commit to”). The items are rated on a 5-point Likert scale (1 = strongly disagree, 5 = strongly agree). Higher scores indicate more active self-identity exploration. The scale demonstrated good internal consistency in the current sample (α = 0.965).

Psychological Resilience (RES). Psychological resilience was measured using the Chinese version of the Connor-Davidson Resilience Scale (CD-RISC), revised by Yu and Zhang (2007). The CD-RISC is one of the most widely used resilience measures across clinical and non-clinical populations. The Chinese version covers three dimensions: hardiness (e.g., “I am able to adapt when changes occur”), strength (e.g., “I tend to bounce back after illness or hardship”), and optimism (e.g., “I can achieve goals despite obstacles”). Twenty items are rated on a 5-point Likert scale (1 = strongly disagree, 5 = strongly agree). Higher scores indicate greater psychological resilience. The scale demonstrated good internal consistency in the current sample (α = 0.979).

Sense of Belonging (SOB). Sense of belonging was assessed using the Psychological Sense of School Membership (PSSM) scale, translated and revised into Chinese by Cheung and Hui (2003). Ten items were selected from the original 18-item scale, covering two dimensions: school belonging (e.g., “I feel like a real part of this school”) and feeling of rejection (e.g., “Sometimes I feel as if I don’t belong here”). Items are rated on a 5-point Likert scale (1 = strongly disagree, 5 = strongly agree). Higher scores indicate a stronger sense of school belonging. Internal consistency was excellent (α = 0.962).

Adjustment Difficulties (AD). Adjustment difficulties were measured using the Chinese College Student Adjustment Scale (CCSAS), developed by Fang et al. (2005) specifically for Chinese college student populations. Four subscales were selected: academic adjustment (e.g., “I find it difficult to keep up with the academic demands of university”), social adjustment (e.g., “I have difficulty making friends in my new environment”), emotional adjustment (e.g., “I often feel anxious or stressed about university life”), and daily-life adjustment (e.g., “I struggle to manage my daily routines independently:”), with 5 items each (20 items total). Items are rated on a 5-point Likert scale (1 = strongly disagree, 5 = strongly agree). Higher scores indicate greater adjustment difficulties. The internal consistency coefficient was 0.975 in the present study.

Neuroticism (NEU). Neuroticism was assessed using the neuroticism subscale of the Chinese Big Five Personality Inventory Brief Version (CBF-PI-B), developed by Wang et al. (2010) specifically for Chinese populations. The subscale assesses emotional instability, anxiety, and mood fluctuation (e.g., “I often feel nervous and uneasy”; “I sometimes feel downhearted and blue”). Eight items are rated on a 5-point Likert scale (1 = strongly disagree, 5 = strongly agree). Higher scores indicate higher neuroticism. Cronbach’s α for the current sample was 0.957.

Extraversion (EXT). Extraversion was assessed using the extraversion subscale of the CBF-PI-B (Wang et al., 2010). The subscale measures sociability, assertiveness, and positive affect (e.g., “I enjoy meeting and talking with people”; “I like to be where the action is”). Eight items are rated on a 5-point Likert scale (1 = strongly disagree, 5 = strongly agree). Higher scores indicate higher extraversion. The scale showed high reliability in the present sample (Cronbach’s α = 0.938).

This study employed a two-stage approach combining Necessary Condition Analysis (NCA) and fuzzy-set Qualitative Comparative Analysis (fsQCA) to examine the antecedent conditions of adjustment difficulties among Chinese university freshmen. To assess common method bias arising from self-report data, Harman’s single-factor test was conducted on all 76 items. The first factor accounted for 38.15% of the total variance, well below the 50% threshold, indicating that common method bias was not a primary concern (Podsakoff et al., 2003).

NCA was conducted using the NCA package in R to address RQ1. NCA examines whether a condition is individually necessary for an outcome, meaning its absence guarantees the absence of the outcome (Dul, 2016a). The Ceiling Regression-Free Disposal Hull (CR-FDH) technique was applied to estimate the ceiling line. Effect size (d ≥ 0.1) was used to determine whether a necessary condition is meaningful, and significance was assessed via permutation tests with 10,000 iterations.

fsQCA was conducted using fsQCA 3.0 to address RQ2. It identifies combinations of conditions sufficient to produce an outcome, accommodating causal complexity through conjunction, equifinality, and asymmetry (Ragin, 2008). Prior to analysis, all conditions and the outcome were calibrated into fuzzy sets. Given that all measures used 5-point Likert scales, calibration anchors were set at 5 (full membership), 3.5 (crossover point), and 1 (full non-membership). On agreement-type Likert scales, a score of 3 reflects neutrality rather than maximum ambiguity regarding set membership. A crossover point of 3.5 better represents the threshold between non-belonging and belonging to the set, consistent with fsQCA practice in psychological research (Ragin, 2008; Schneider & Wagemann, 2012).

The analysis proceeded in three steps. First, single necessary conditions were examined within fsQCA using a consistency threshold of 0.90. Second, a truth table was constructed, and configurations with fewer than 3 cases were excluded. A consistency threshold of 0.80 was applied to identify sufficient configurations. Third, the Standard Analysis procedure was used to derive parsimonious, intermediate, and complex solutions. Both high adjustment difficulties (risk profiles) and low adjustment difficulties (protective profiles) were analyzed separately to capture asymmetric causal relationships.

Descriptive statistics for all study variables are presented in Table 3. Sense of belonging had the highest mean (M = 3.69, SD = 0.83), while neuroticism (M = 3.29, SD = 0.91) and adjustment difficulties (M = 3.30, SD = 0.72) showed comparatively lower scores.

Necessary condition analysis was used to assess whether any single condition is necessary for adjustment difficulties. A condition is considered necessary when the effect size exceeds 0.1, and the p-value is significant (Dul, 2016b). Table 4 presents the results for all five conditions based on the CR-FDH ceiling technique.

As shown in Table 4, none of the conditions meet the necessary condition threshold. Effect sizes ranged from 0.000 to 0.025, all below 0.1, and no p-value reached significance. The NCA plots (Figure 1) further support these findings. The ceiling lines for self-identity exploration and sense of belonging are flat at the top of the scope, indicating no meaningful constraint on the outcome. For psychological resilience and neuroticism, small ceiling zones appear in the upper-left region of the plots, but the effect sizes remain negligible. For extraversion, the ceiling line is nearly horizontal, with data points spread across the full range of the outcome.

Overall, none of the five conditions constitutes a necessary condition for adjustment difficulties among Chinese university freshmen. This finding suggests that adjustment difficulties result from combinations of conditions rather than any single factor, supporting the need for configurational analysis.

The consistency threshold was set at 0.80, and the frequency threshold at 3. Both high and low adjustment difficulties were analyzed separately. The complex, parsimonious, and intermediate solutions were obtained. Following established practice, the intermediate solution is used as the primary basis for interpretation, with the parsimonious solution used to identify core conditions. In the present analysis, the intermediate and parsimonious solutions were identical, indicating that all conditions in the identified configurations are core conditions. The results are presented in Table 5.

Analysis of High Adjustment Difficulties (Risk Profiles). Three configurational paths were identified for high adjustment difficulties. Each path has a consistency above 0.80. The overall solution consistency is 0.940, and solution coverage is 0.783, meaning these three paths explain 78.3% of cases with high adjustment difficulties.

Configuration H1 (absent self-identity exploration * absent psychological resilience * absent extraversion) can be characterized as a “multi-resource deficit risk configuration”. It indicates that the simultaneous absence of self-identity exploration, psychological resilience, and extraversion is sufficient to produce high adjustment difficulties. This configuration has a raw coverage of 0.650, explaining 65.0% of cases. Freshmen who have not developed a clear sense of self are less able to set goals and make meaning of their university experience. Without resilience, they struggle to recover from setbacks. Combined with introversion, they are less likely to seek social support or engage proactively with their new environment, making successful adjustment difficult. From a COR perspective, the simultaneous absence of three resources across personal, psychological, and social domains triggers a resource loss spiral (Hobfoll, 1989), in which the lack of one resource accelerates the depletion of others, collectively rendering successful adjustment unlikely.

Configuration H2 (absent self-identity exploration * absent sense of belonging * psychological resilience) represents an “identity-belonging resource deficit risk configuration”. It shows that when self-identity exploration and sense of belonging are both absent, high adjustment difficulties occur even when psychological resilience is present. This configuration has a raw coverage of 0.523, explaining 52.3% of cases. This finding suggests that resilience alone is insufficient to protect against adjustment difficulties. Without a clear sense of self and a feeling of connectedness to the university, freshmen may lack the motivational foundation needed to engage with academic and social demands, regardless of their coping capacity. This pattern reflects resource insufficiency (Hobfoll, 1989). A single resource cannot compensate for the simultaneous absence of identity and belonging resources, highlighting the boundary conditions of resilience as a protective factor.

Configuration H3 (absent self-identity exploration * absent psychological resilience * neuroticism) reflects a “resource deficit and emotional vulnerability risk configuration”. It combines the absence of self-identity exploration and psychological resilience with the presence of neuroticism. This configuration has a raw coverage of 0.634, explaining 63.4% of cases. When freshmen lack both identity clarity and resilience, emotional instability further compounds their difficulties. Neurotic individuals tend to interpret ambiguous situations negatively and experience stronger emotional reactions to stressors. In the context of university transition, where uncertainty is high, this pattern is particularly likely to produce adjustment difficulties. Within the COR framework, the co-absence of identity and resilience resources, combined with elevated neuroticism, creates a compounded loss spiral (Hobfoll, 1989) in which emotional vulnerability both results from and further accelerates resource depletion.

The absence of self-identity exploration appears as a shared element across all three risk configurations. This suggests its particular relevance to high adjustment difficulties among Chinese university freshmen.

Analysis of Low Adjustment Difficulties (Protective Profiles). Three configurational paths were identified for low adjustment difficulties. The overall solution consistency is 0.887, and solution coverage is 0.905. This means these three paths explain 90.5% of cases with low adjustment difficulties.

Configuration L1 (self-identity exploration * sense of belonging) represents an “identity-belonging resource synergy protective configuration”. It indicates that the co-presence of self-identity exploration and sense of belonging is sufficient to protect freshmen from adjustment difficulties. This configuration has the highest raw coverage of 0.857, explaining 85.7% of cases. Freshmen who have a clear sense of who they are and feel accepted within their university community are better equipped to navigate academic and social challenges. The sense of belonging provides a stable social base, while identity clarity provides direction and purpose. From a COR perspective, the combination of an internal resource (identity clarity) and an external resource (school belonging) generates a resource gain spiral (Hobfoll, 1989), in which each resource reinforces the other, collectively producing a robust protective effect.

Configuration L2 (self-identity exploration * psychological resilience) reflects an “identity-resilience resource synergy protective configuration”. The presence of self-identity exploration combined with psychological resilience forms a sufficient protective pathway. This configuration has a raw coverage of 0.750, explaining 75.0% of cases. Identity clarity helps freshmen set meaningful goals, while resilience enables them to persist through difficulties. Together, these two resources allow freshmen to adapt effectively to the demands of university life without needing strong social support. Within the COR framework, the conjunction of two personal characteristic resources allows them to substitute for the absence of relational resources, consistent with the principle of resource substitutability (Hobfoll, 2011).

Configuration L3 (sense of belonging * psychological resilience * absent neuroticism * extraversion) represents a “relational-emotional resource substitution protective configuration”. It combines a sense of belonging, psychological resilience, and extraversion with the absence of neuroticism. This configuration has a raw coverage of 0.541, explaining 54.1% of cases. This pattern suggests that social engagement and emotional stability can together compensate for the absence of strong identity exploration. Extraverted, emotionally stable, and resilient freshmen are able to draw on their interpersonal and personal resources to facilitate adjustment, even when their sense of self is not yet well-developed. This configuration illustrates resource substitutability (Hobfoll, 1989). Relational and emotional resources collectively substitute for the absence of identity resources, demonstrating that multiple pathways to successful adjustment exist.

Self-identity exploration appears in two of the three protective configurations. This reinforces its consistent presence across the majority of protective pathways. These results also demonstrate equifinality. Different combinations of conditions can lead to the same outcome of low adjustment difficulties.

Robustness Test. To examine the robustness of the fsQCA results, two tests were conducted. First, the consistency threshold was raised from 0.80 to 0.85. The configurations identified under the higher threshold were compared with the original results. The risk profiles and protective profiles remained stable. No new configurations emerged and no original configurations disappeared.

Second, a sensitivity analysis was conducted to examine whether the results varied with different calibration anchor selections. The crossover point was adjusted from 3.5 to 3.0 and 4.0. The full membership anchor (5) and full non-membership anchor (1) were kept unchanged. Under a crossover of 3.0, all three risk configurations remained consistent (H1 = 0.993, H2 = 0.998, H3 = 0.994). The consistency of the protective configurations was reduced, as lower crossover values widen set boundaries and admit more cases into the self-identity exploration and sense of belonging sets, reducing configuration purity. Under a crossover of 4.0, two risk configurations remained stable (H2 = 0.944, H3 = 0.906), while H1 fell marginally below the threshold (0.777). This is because higher crossover values raise the membership standard for absence conditions, reducing the number of cases that simultaneously qualify for absent self-identity exploration, absent psychological resilience, and absent extraversion. All three protective configurations exceeded 0.80 (L1 = 0.986, L2 = 0.989, L3 = 0.996). Across both alternative crossover settings, the absence of self-identity exploration remained a consistent element in the risk configurations. The consistent relevance of self-identity exploration was preserved in the majority of protective pathways. The principal findings are therefore not an artifact of the specific calibration anchor selected.