Effects of future time perspective on depression in college students: the mediating role of emotional intelligence and moderating role of physical exercise

Abstract

Objective

This study investigates how emotional intelligence mediates the link between future temporal orientation and depressive symptoms in university students and explores whether physical activity moderates this connection.

Method

Data were collected from 1,014 undergraduate students (490 males and 524 females) across three universities in Fujian Province, China, between 1 March and 5 July 2024. Participants were selected via random sampling and completed the Future Time Perspective Scale, Emotional Intelligence Scale, Physical Activity Rating Scale, and Epidemiologic Studies Depression Scale. Statistical analyses included Pearson’s correlation, linear regression, and moderated mediation analysis (PROCESS Model 7) using SPSS 22.0.

Results

(1) Future time perspective significantly and negatively predicted depression (β = -0.32, p < 0.001). (2) Emotional intelligence partially mediated the association between future time perspective and depression (indirect effect = -0.11, SE = 0.02, 95% CI [-0.15, -0.08]). (3) Physical exercise moderated the first-stage path of the mediation model (FTP → EI). Simple slope analyses showed that the FTP–EI association was significant at both low (M − 1 SD) and high (M + 1 SD) levels of physical exercise, but was stronger at high physical exercise (simple slope: β = 0.41, p < 0.01) than at low physical exercise (simple slope: β = 0.25, p < 0.01).

Conclusion

Future time perspective influences depression both directly and indirectly through emotional intelligence. Additionally, physical exercise enhances the predictive effect of future time perspective on emotional intelligence, suggesting that active individuals exhibit a stronger link between future-oriented thinking and emotion regulation.

Introduction

The mental health of college students has become a growing global concern [1, 2]. Depression, a key indicator of mental health, can manifest as a motivational deficit, weakened determination, sleep irregularities, impaired academic performance, and in severe cases, maladaptive behaviors such as self-harm, aggression, addiction, and loss of appetite [3, 4]. According to the World Health Organization, depression is projected to become one of the leading global health burdens by 2030 [5]. College students are undergoing the developmental transition from adolescence to adulthood, and as such experience heightened emotion fluctuations. Thus, they are considered a high-risk group for depression [6]. Previous studies have reported that depressive symptoms and major depressive disorder are more prevalent among college students than in the general population [2, 7, 8]. How individuals perceive their future plays a crucial role in emotional well-being. Specifically, viewing the future as limited may heighten anxiety and increase the likelihood of a depressive affect. Prior research has primarily focused on factors such as stress, life events, cognitive distortions, interpersonal relationships, and coping styles in relation to college students’ depression [9–13], with only limited attention being paid to the role of future time perspective (FTP) and its underlying mechanisms. Investigating how FTP influences depression and exploring the psychological pathways involved is therefore essential for developing effective preventive strategies and interventions.

Future time perspective and depression

FTP refers to an individual’s cognitive tendency to perceive their remaining lifespan as either limited or open-ended [14]. As a cognitive framework, FTP guides how people regulate emotions, set goals, and allocate psychological resources. According to socioemotional selectivity theory [15], individuals’ perceptions of the future shape their goal priorities, activity choices, and emotion regulation [16]. Those who view the future as open-ended tend to adopt a forward-looking orientation characterized by exploration, planning, and long-term goal pursuit [17], promoting greater life satisfaction, a positive affect, and stronger sense of purpose [18]. Conversely, perceiving the future as constrained directs attention toward immediate emotional gratification and selective engagement in meaningful but limited activities, often accompanied by a heightened negative affect and reduced well-being [18, 19]. Thus, a restricted or pessimistic view of the future can be a risk factor for poor psychological adjustment, manifesting as depression and anxiety. Consistent with prior findings showing a negative association between FTP and depression [20], we propose the following hypothesis:

• H1: FTP negatively predicts depression among college students

Emotional intelligence as a mediator

Although prior research has demonstrated a significant association between FTP and depression, the underlying mechanism connecting the two remains insufficiently understood. Emotional intelligence (EI) refers to the ability to perceive, understand, and regulate both one’s own and others’ emotions, and the capacity to apply this emotional knowledge effectively in daily life [21, 22]. Individuals with high FTP tend to emphasize long-term goals and adopt problem-focused regulation strategies, such as planning and proactive coping. Their future-oriented mindset promotes emotional awareness, reflective processing, and adaptive regulation, skills that facilitate active problem-solving rather than passive avoidance. In contrast, individuals with low FTP lack future-oriented motivation and are more likely to rely on emotion-focused strategies (e.g., avoidance, suppression) and experience greater short-term distress. Thus, FTP is positively associated with EI [23]. High EI enables individuals to manage stress more effectively [24], adapt flexibly to challenges [25], and regulate emotional responses to both internal and external demands [26]. Such individuals maintain emotional balance, cope constructively with adversity, and exhibit greater psychological resilience, thereby reducing depressive symptoms [27]. Therefore, FTP may enhance EI, and in turn alleviate depression. Thus, we propose the following hypothesis:

• H2: FTP influences depression through the mediating role of EI.

Physical exercise as a moderator

The relationship between TFP and EI may be influenced by external behavioral factors such as physical exercise and could vary depending on the level of college students’ physical activity. Physical exercise is generally defined as any bodily movement produced by skeletal muscles that results in energy expenditure [28]. Research has identified a positive correlation between physical exercise and EI. Wang et al. [29] found that regular physical activity enhances EI among college students, while Zhu demonstrated that moderate-intensity exercise improves emotion regulation and emotional perception in primary school students [30, 31]. Similarly, Ruiz-Ariza et al. [32] showed that cooperative high-intensity intermittent exercise boosts EI in inactive adolescents.

Previous research has found that FTP is associated with physical exercise [33]. From a temporal self-regulation perspective, both FTP and physical exercise represent adaptive self-regulatory processes that connect present behavior with future outcomes. FTP reflects future-oriented cognition and motivation, guiding individuals to pursue long-term goals and regulate current actions according to future expectations. In contrast, physical exercise represents present-oriented behavioral regulation, requiring individuals to exert effort in the present to achieve the desired physical and psychological benefits in the future. These two constructs complement one another across temporal domains. FTP provides cognitive–motivational direction, while physical exercise embodies the behavioral realization of future-oriented goals. According to socioemotional selectivity theory, individuals with a strong FTP tend to prioritize growth-oriented goals and engage in activities that foster long-term well-being. Physical exercise can be seen as a behavioral manifestation of this orientation, promoting emotional and cognitive flexibility through physiological activation and an enhanced positive affect. Furthermore, based on the protective– protective model [34], FTP and physical exercise may jointly strengthen EI. Each could serve as a protective factor that buffers against psychological distress and fosters adaptive functioning. Physical exercise may amplify the positive effect of FTP on EI by improving emotion regulation, stress tolerance, and self-efficacy. In other words, individuals with higher FTP who also maintain regular physical activity are likely better equipped to manage emotions and sustain a positive psychological state. Therefore, we propose the following hypothesis:

• H3: Physical exercise moderates the first stage of the mediation pathway (the path from FTP to EI)

The present study

Although FTP has been identified as a protective factor against depression, its underlying mechanisms remain underexplored. Prior research has not examined how college students’ FTP, EI, and physical exercise interact within a single framework. Therefore, this study investigates the mediating role of EI in the relationship between FTP and depression, and tests whether physical exercise moderates the first-stage path from FTP to EI. The proposed conceptual model is illustrated in Fig. 1. In summary, this study clarifies how cognitive (FTP), emotional (EI), and behavioral (physical exercise) factors jointly contribute to college students’ mental health and provides evidence-based insights for intervention design.

Fig. 1.

Proposed moderated mediation model

Method and instruments

Participants and procedure

This study adopted a cluster sampling approach to survey students across different academic years at three comprehensive universities. Participants were required to have had no prior involvement in similar studies and offered a small gift upon completing the questionnaire. After obtaining informed consent from the students, a total of 1,100 undergraduates participated in the survey, yielding 1,014 valid responses (an effective response rate of 93.66%). The sample was comprised of 490 males and 524 females, with 273 freshmen, 331 sophomores, 259 juniors, and 151 seniors. The participants’ mean age was 19.83 years (SD = 1.19).

Measurements

Future time perspective

This study utilized the Chinese adaptation of the Future Time Perspective subscale of the Zimbardo Time Perspective Inventory (ZTPI) [35], originally developed by Zimbardo [36]. Items assess goal-directed planning (e.g., “I establish clear objectives and actionable plans when pursuing goals”) and persistence (e.g., “I maintain effort in challenging tasks if they contribute to self-improvement”). The subscale is comprised of five items rated on a five-point Likert scale (1 = strongly disagree to 5 = strongly agree); higher scores reflect greater future orientation. Internal consistency for this measure was acceptable for the current sample (α = 0.77).

Emotional intelligence

This study employed the Chinese version of the Emotional Intelligence Scale developed by Wong and Law [37, 38], which consists of 16 items covering four dimensions: emotion self-appraisal, appraisal of others’ emotions, use of emotion, and regulation of emotion. Sample items include: “When I am angry, I can calm down very quickly”. The scale is rated on a seven-point Likert scale ranging from 1 (strongly disagree) to 7 (strongly agree). In the current study, the scale demonstrated good internal consistency, with a Cronbach’s α = 0.88 for the total scale and 0.81, 0.84, 0.79, and 0.83 for the four subscales of self-emotion appraisal, appraisal of others’ emotions, use of emotion, and regulation of emotion, respectively.

Physical exercise

The Physical Activity Rating Scale is a validated instrument used to assess an individual’s level of physical activity. Developed based on Liang’s [39] modifications, this scale evaluates three key dimensions: exercise intensity, duration, and frequency. All items are measured on a five-point Likert-type scale (1 = strongly disagree to 5 = strongly agree). The composite physical activity score is derived through the following equation: Total Score = Intensity × (Duration—1) × Frequency, yielding a possible range of zero to 100 points. A maximum score of 100 is obtained when all three dimensions reach their highest rating levels, representing the greatest overall physical activity. Based on the total physical activity score, participants were classified into three activity levels: low (≤ 19), moderate (20–42), and high (≥ 43) [40]. Higher scores indicate greater levels of physical engagement. In the current study, the scale demonstrated good internal consistency (Cronbach’s α = 0.82).

Depression

The Center for Epidemiologic Studies Depression Scale (CES-DS) [41] was administered to assess participants’ depressive symptoms. This 10-item scale has demonstrated good reliability and validity among Chinese adolescent populations [42]. The items measure psychological states experienced during the past week (e.g., “I was bothered by things that usually don't bother me”) and is rated on a four-point Likert-type frequency scale: 0 (rarely/none of the time), 1 (some/a little of the time), 2 (occasionally/moderate amount), and 3 (most/all of the time), with higher aggregate scores reflecting greater depressive symptom severity. The scale demonstrated good internal consistency for the current study (Cronbach’s α = 0.79).

Statistical methods

This study began by computing descriptive statistics and examining bivariate correlations among the variables. Subsequently, mediation, moderation, and moderated mediation effects were analyzed using Hayes’ PROCESS 3.4 macro (Model 4 and Model 7) in SPSS [43]. For the analysis, the bias-corrected bootstrap method was employed, generating 95% confidence intervals (CI) based on 5,000 resampled iterations. Statistical significance was determined when the CI excluded zero. Gender, age, and grade were included as covariates because prior studies have shown that these demographic characteristics are associated with emotional intelligence, physical exercise, and depression [44–47]. Thus, all models were adjusted for these variables to reduce potential confounding.

Results

Common method bias and test

The data in this study were collected using self-reported questionnaires, a process that may introduce common method variance. Potential common method bias was assessed via Harman’s single-factor test [48]. The analysis identified five factors with eigenvalues greater than 1 in the unrotated factor solution, collectively explaining 55.91% of the total variance. The largest factor accounted for 22.21% of the variance, which is under the 40% cutoff value. Thus, common method bias was not considered a significant issue in this study.

Preliminary analyses

Table 1 presents the means, standard deviations, and correlations among the variables employed in each analysis. As expected, FTP was moderately positively correlated with EI (r = 0.41), moderately negatively correlated with depression (r = − 0.32), and weakly positively correlated with physical exercise (r = 0.21). EI was significantly negatively correlated with depression (r = −0.35) and significantly positively correlated with physical exercise (r = 0.26). Physical exercise was negatively correlated with depression (r = −0.20). Thus, Hypothesis 1 was supported.

Table 1.

Descriptive statistics and correlation analysis

Variable	1	2	3	4
1. FTP	1
2. EI	0.41***	1
3. Physical exercise	0.21***	0.26***	1
4. Depression	−0.32***	−0.35***	−0.20***	1
Mean	3.58	4.75	2.53	1.81
SD	0.60	1.18	0.88	0.41

M Mean, SD Standard deviation, FTP Represents Future Time Perspective, EI Represents Emotional Intelligence

^*** p < 0.001

Mediation effect of emotional intelligence

We conducted a mediation analysis using Hayes’ PROCESS Model 4 (with 5,000 bootstrap samples) to examine whether EI mediated the relationship between FTP and depression among college students, while controlling for gender, age, and grade. First, FTP showed a significant negative total effect on depression (β = −0.32, p < 0.001). Second, when including EI as a mediator, FTP maintained both a significant positive effect on EI (β = 0.40, p < 0.001) and a significant (though reduced) negative effect on depression (β = −0.21, p < 0.001), while EI itself demonstrated a significant negative effect on depression (β = −0.27, p < 0.001). Finally, the mediation analysis confirmed EI’s significant mediating role, with an indirect effect of −0.11 (accounting for 34.38% of the total effect) and a 95% bootstrap confidence interval of [−0.15, −0.08] that did not include zero (see Tables 2 and 3).

Table 2.

Testing for mediation effect of FTP on depression

Predictors	Model 1 (Depression)				Model 2 (EI)				Model 3 (Depression)
	β	t	Boot LLCI	Boot ULCI	β	t	Boot LLCI	Boot ULCI	β	t	Boot LLCI	Boot ULCI
Gender	0.02	0.47	−0.52	−0.34	−0.02	−0.42	−0.15	0.09	0.03	0.61	−0.08	0.16
Age	0.04	0.28	−0.37	0.68	0.04	0.65	−0.08	0.16	0.05	0.76	−0.08	0.17
Grade	−0.06	−0.57	−0.85	0.38	−0.05	−0.74	−0.20	0.09	−0.07	−0.98	−0.22	0.07
FTP	−0.32***	−9.71			0.40***	12.85	0.34	0.46	−0.21***	−6.01	−0.27	−0.14
EI									−0.27***	−7.89	−0.34	−0.20
R2	0.10				0.17				0.16
F	23.74***				41.90***				32.82***

Boot LLCI represents Bootstrapped Lower Limit Confidence Interval

Boot ULCI Bootstrapped Upper Limit Confidence Interval

^*** p < 0.001

Table 3.

Decomposition of total, direct, and indirect effects

	Effect	SE	Boot LLCI	Boot ULCI	Proportion
Total effect	−0.32	0.04	−0.52	−0.34
Direct effect	−0.21	0.03	−0.27	−0.14	65.62%
Indirect effect	−0.11	0.02	−0.15	−0.08	34.38%

Boot LLCI represents Bootstrapped Lower Limit Confidence Interval

Boot ULCI Bootstrapped Upper Limit Confidence Interval

Moderating effect of physical exercise

A moderated mediation analysis using PROCESS Model 7 [43] was used to test Hypothesis 3, revealing three significant effects. FTP negatively predicted depression (β = −0.21, p < 0.001), the FTP × Physical Exercise interaction significantly influenced EI (β = 0.11, p < 0.05), and EI showed a negative association with depression (β = −0.27, p < 0.001). These results demonstrate that physical exercise moderates the first stage of the mediation pathway (the path from FTP to EI), providing support for Hypothesis 3 (see Table 4).

Table 4.

Testing a first-stage moderated mediation model of the FTP–depression association via emotional intelligence

Predictors	Model 1(EI)				Model 2(Depression)
	β	t	Boot LLCI	Boot ULCI	β	t	Boot LLCI	Boot ULCI
Gender	−0.04	−0.65	−0.16	0.08	0.04	0.61	−0.09	0.16
Age	0.05	0.87	−0.07	0.17	0.05	0.75	−0.07	0.17
Grade	0.01	0.21	−0.21	0.07	−0.07	−0.98	−0.22	0.07
FTP	0.34***	10.83	0.28	0.41	−0.21***	−6.01	−0.27-	0.14
Physical Exercise	0.17	5.51	0.11	0.24
FTP × Physical Exercise	0.10**	3.26	0.03	0.15
EI					−0.27***	−7.89	−0.34	−0.20
R2	0.21				0.38
F	36.87***				33.35***

Boot LLCI represents Bootstrapped Lower Limit Confidence Interval

Boot ULCI Bootstrapped Upper Limit Confidence Interval

^**p < 0.01.***p < 0.001

A simple slope analysis was used to examine the moderating role of physical exercise. As shown in Fig. 2, the effect of FTP on EI was assessed at two levels of physical exercise: low (M – 1 SD) and high (M + 1 SD). The results indicated that FTP was positively associated with EI in both groupsin both groups. However, this effect was stronger among participants engaging in high levels of physical exercise (β = 0.41, p < 0.001), as compared to those who engaged in less physical exercise (β = 0.25, p < 0.001). These findings support our hypothesis that higher levels of physical exercise strengthen the positive association between FTP and EI. Specifically, the increase in EI with rising FTP was more pronounced in the high physical exercise group than in the low physical exercise group.

Fig. 2.

The moderating effect of physical exercise on the relationship between FTP and EI

Discussion

This study, grounded in socioemotional selectivity theory and the protective–protective model, examined the mediating role of EI in the relationship between FTP and depression, as well as the moderating effect of physical exercise in this association. The findings contribute to a deeper understanding of how FTP influences depression through the factor of EI, and whether the relationship between FTP and EI varies across different levels of physical exercise (moderating effect). These insights hold significant implications for interventions and prevention strategies targeting depression among college students. Importantly, this study makes several novel contributions. To our knowledge, it is the first to construct and empirically test a moderated mediation model linking FTP, EI, and depression within a college student population. By integrating socioemotional selectivity theory with the protective–protective model, this study provides a new theoretical lens to explain how cognitive-motivational (FTP), emotional (EI), and behavioral (physical exercise) factors jointly shape mental health outcomes. Moreover, the identification of EI as a psychological mechanism and physical exercise as a behavioral buffer offers new directions for the design of targeted interventions aimed at enhancing mental health and reducing depressive symptoms in young adults.

This research found that FTP exerts a significant protective effect against depression among college students. Specifically, higher levels of FTP are associated with lower levels of depressive symptoms, a conclusion consistent with previous research [20, 49]. The results indicate that as a cognitive and prospective orientation toward future life and career planning, FTP serves as a protective factor for mental health. The reason for this is that FTP reflects students’ clear awareness of future goals and their confidence in achieving them [50]. College students with high FTP can rationally plan their career development, set reasonable goals, and work toward them; they are more motivated and goal-oriented, enabling them to better cope with challenges and stress [51]. In contrast, students lacking FTP often feel lost about the future, making them more prone to anxiety and helplessness and thereby increasing their risk of depression. The results indicate that developing FTP effectively alleviates depressive symptoms in university students, offering empirical support for depression interventions that prioritize this psychological construct.

The results support our hypothesized mediation model, with EI partially explaining the protective effect of FTP against depression. Specifically, college students with higher levels of FTP tend to demonstrate better EI, which in turn reduces their risk of depression. To our knowledge, this is the first study to investigate the role of EI in the relationship between FTP and depression among college students. The findings support EI’s function as a crucial psychological resource bridging temporal cognition and emotional well-being [52]. Previous studies have also indicated that elderly consumers with an expansive FTP demonstrate greater cognitive, reflective, and compassionate dimensions of wisdom, consequently developing enhanced EI and engaging in more problem solving [53]. This mediating effect can be explained by socioemotional selectivity theory. Individuals with a clear future-facing orientation prioritize developing emotion regulation abilities to cope with challenges in achieving long-term goals [54]. A strong FTP motivates students to actively cultivate emotion-related skills such as stress management and empathy, which help buffer the impact of negative life events [55]. Conversely, individuals lacking FTP often exhibit deficient emotion regulation strategies, making them more vulnerable to depression when facing adversity [49]. Therefore, as academic administrators addressing depression prevention and management in university students, we should not focus solely on enhancing FTP levels, but also prioritize cultivating EI as a critical bridging mechanism, thereby improving the efficacy of depression interventions.

Furthermore, this study found that the first half of the mediating effect between FTP and depression among college students was moderated by physical exercise. To our knowledge, this is the first empirical study to demonstrate physical exercise’s role in moderating the relationship between FTP and EI. The results indicate that the positive association between FTP and EI strengthens with increased exercise frequency, supporting the theoretical propositions of the protective-protective model [33]. Specifically, college students who engage in regular exercise and possess high FTP tend to demonstrate greater EI, which in turn has a substantial indirect effect on alleviating depression. Regular physical exercise enhances college students’ self-regulation and psychological resilience, creating a synergistic effect with the goal persistence fostered by FTP [56, 57], thereby reducing depressive symptoms. In addition, the social interactions and sense of achievement gained during physical activity may further strengthen the positive impact of FTP on EI [58]. Therefore, when college students experience stress, FTP in physically active students serves as a more powerfully beneficial predictor of EI. These findings suggest that educators should emphasize both FTP development and regular physical exercise, as this dual approach enhances the capacity for EI, thereby improving the effectiveness of depression prevention and intervention.

Implications and limitations

The findings of this study provide valuable insights into the protective role of FTP against depression and offer important implications for designing university mental health interventions. Specifically, FTP was found to negatively predict depression, suggesting that enhancing FTP may help reduce students' depressive symptoms. Educators should strengthen students' FTP by guiding them to set clear goals, break down long-term objectives into actionable steps, and use time-management tools (e.g., schedules, task lists) to improve planning skills. Encouraging regular reflection and plan adjustment would also help students appreciate long-term planning and enhance motivation. Furthermore, the mediating role of EI underscores the importance of integrating EI training into mental health education. Emotion management courses should include awareness exercises to help students recognize their own and others’ emotions. Scenario-based training, cognitive reappraisal, and mindfulness practices would help foster empathy, adaptability, and emotion regulation. Practical activities such as journaling, role-playing, and group reflection would further help students identify emotion patterns and develop adaptive coping strategies, thereby reducing vulnerability to depression. In addition, the moderating effect of physical exercise identified in the present research highlights the value of incorporating physical activity into campus mental health initiatives. Health awareness could be promoted through wellness lectures, and motivation sustained through campus sporting events and tiered reward systems (e.g., exercise point redemption), fostering a sustainable exercise culture characterized by scientific guidance, peer support, habit formation, and overall enjoyment. Thus, the findings outlined here support a multilevel intervention model for university mental health promotion that integrates cognitive (FTP), emotional (EI), and behavioral (physical exercise) components, offering practical strategies for educators and counselors to enhance students’ well-being and prevent depression.

This study has several limitations. First, the ZTPI used in this research assesses FTP as a unidimensional construct, which may have limited the ability to capture the nuanced influence of different FTP components on depression. Specifically, different facets of FTP (e.g., future orientation, planning, and goal setting) may relate to emotional intelligence (EI) and depression through partially different pathways. Future studies should employ multidimensional measures such as the Five-Factor Future Time Perspective Scale to explore how specific dimensions of FTP differentially relate to depression and its underlying psychological mechanisms. Second, the reliance on self-reported questionnaire data from college students may have introduced response biases. Subsequent studies should incorporate multi-method assessments to enhance validity. Third, the cross-sectional design limits causal inferences and longitudinal prediction. Future work should employ longitudinal designs to track temporal dynamics. Finally, while we examined key mediators/moderators, depression in college students involves multifactorial influences.

Conclusion

This study examined the psychological mechanisms underlying the relationship between FTP and depression among college students, establishing a structural model that incorporates FTP, EI, physical activity, and depressive symptoms. The findings indicate that FTP influences student depression through both direct pathways and indirect mediation via EI. Furthermore, physical activity significantly moderated the first stage of the mediation pathway from FTP to EI, with a stronger FTP–EI link observed among students engaging in higher levels of physical exercise.

Abbreviations

FTP

Future Time Perspective

EI

Emotional intelligence

ZTPI

The Zimbardo Time Perspective Inventory

CES-DS

The Center for Epidemiologic Studies Depression Scale

CI

Confidence Intervals

Boot LLCI

Bootstrapped Lower Limit Confidence Interval

Boot ULCI

Bootstrapped Upper Limit Confidence Interval

Authors’ contributions

YH conceptualized and designed the project. YH and JC acquired and managed the data and performed statistical and data analysis.YH drafted the manuscript. YH, JC and ML revised the manuscript. All authors contributed to the article and approved the submitted version.

Funding

This research was funded by Social Science Planning Fund Program, Fujian Province (FJ2025MGCA045).

Data availability

The datasets utilized and/or analyzed during the present study are accessible upon reasonable request from the corresponding author.

Declarations

Ethics approval and consent to participate

Approval for this study was given by the ethics committee of Fujian Medical University and written informed consent was obtained from the participants. All participants provided written informed consent. All methods were performed following the Declarations of Helsinki.

Consent for publication

Not applicable.

Competing interests

The authors declare no competing interests.