Relationship between Mindfulness and Burnout among Chinese Pilots: Multiple Mediation through Fatigue and Proactive Coping

Objective: The present study aimed to examine a possible relationship between mindfulness and burnout among Chinese civil pilots, and to investigate the mediating effects of fatigue and proactive coping. Background: Based on the perspective of the extended job demand–resource model, the current study has extended prior research for identifying the mechanism underlying the roles of personal resource and personal stress in the association between mindfulness and burnout. Method: A representative sample of 319 civil pilots drawn from the China Southern Airlines accomplished self-administrated questionnaires. Structural Equation Modeling (SEM) was used to test the hypothesized multiple mediation model with Mplus 8.3. Results: Results addressed consistent evidence that mindfulness would play an important part in relieving and preventing burnout. A multiple mediation model showed that mindfulness exerted its indirect effect on burnout through fatigue and proactive coping, χ 2 = 940.495, df = 660, χ 2 /df = 1.425, TLI = .940, CFI = .944, SRMR = .045, RMSEA = .037. Moreover, fatigue mediated the effect of mindfulness on burnout (β = -.074, 95%CI = -.106 to -.036), whereas proactive coping mediated the association between mindfulness and burnout (β = -.842, 95%CI = -1.215 to -.635). Consequently, �ndings corroborated a predictive role of fatigue and proactive coping, both independently and jointly, in the indirect effect that mindfulness exerted effects on burnout. Conclusion: Theoretical implications in the extended job demand-resource model and practical recommendations for mindfulness training practice and fatigue reduction program were discussed.


Introduction
With the improvement of aircraft technology and automation systems, there has been a series of human errors that have caused approximately 80% of accidents and incidents (Harris et al., 2001), such as Asiana Flight 214, the German Typhoon and Learjet collision, and Air France Flight 447.Human factors, such as mental health, may play an important part in aviation safety (Kelly & Efthymiou, 2019).Pilots who suffered from mental distress will result in low work performance, temporary or permanent grounding of aircraft, and serious accidents or safe-related incidents (Fanjoy et al., 2010).Among mental health factors, burnout is described as a syndrome of emotional exhaustion, depersonalization, and sense of lack of personal accomplishment (Maslach et al., 1996).Research has shown that 32.6% of regional airline pilots were identi ed as high burnout candidates (Fanjoy et al., 2010), and 14%-33% of the Air Force drone operators reported to be suffering from high levels of exhaustion (Chappelle et al., 2014), suggesting a high prevalence of burnout among pilots.It is well established that burnout can be a major contributing factor in ineffective job performance, job dissatisfaction, and turnover intention (Ceyhun & Ozbag, 2014;Fanjoy et al., 2010;Mengenci, 2014).Hence, it can be reasonably argued that burnout may have an adverse in uence on occupational health and ight safety in aviation.
Studies on pilot burnout have not yet focused on mindfulness that is broadly conceptualized as the process of paying attention to cultivate awareness of the experience of the moment in a nonjudgmental or non-evaluate accepting way (Brown & Ryan, 2003).It is conceptualized as both personality trait and skill that can be cultivated through training and meditation.Research reporting decreased burnout after mindfulness training is in accordance with the strong evidence reported in meta-analysis of interdisciplinary literature that mindfulness practice is effective for reducing burnout (dos Santos et al., 2016;Luken & Sammons, 2016).More importantly, mindfulness, measured by MAAS (Mindful Attention Awareness Scale) and FFMQ (Five Facet Mindfulness Questionnaire), was found to moderate the negative effects of work-related stress on depression, anxiety, and burnout (Taylor & Millear, 2016;Westphal et al., 2015).Furthermore, mindfulness may serve as a resilience-promoting factor to enhance positive mental health factors such as hope, optimism, wellness, work well-being, life satisfaction, and self-esteem, but also mitigate symptoms of depression, anxiety, and burnout (Brown & Ryan, 2003;dos Santos et al., 2016;Schultz et al., 2015;Sears & Kraus, 2009;Westphal et al., 2015).The robust predictive effect of mindfulness training on performance-related anxiety has strengthened in high-performance combat aviation population (Meland, Fonne, et al., 2015).Although research has rarely examined the impact of mindfulness on burnout among pilots, based on ndings mentioned above, it is reasonable to infer that mindfulness would be a predictive factor that can protect against and reduce risk of pilots' burnout.
A range of individual, situational and environmental risk factors have been identi ed as possible contributing factors to burnout among pilots.Studies have revealed that individual factors, such as flight time and crewmember position, situational factors such as work overload and adverse weather, and organizational factors such as aircraft maintenance issues and fair wages are in uential factors on burnout (Fanjoy et al., 2010;Kearney, 2008).Situational factors and organizational factors explain how job demands and resources in uence levels of burnout (Searle & Lee, 2015).From this, it is reasonable to believe that pilots who have adapted poorly to rapid job demands from both ight safety and economic effectiveness may have far more burnout.From the perspective of the extended job demand-resource model, personal resources and personal stress, may account for the reasons why some are less prone to experience burnout compared others when exposed to di cult job demands and lack of job resources (Pennie et al., 2018).However, the majority of existing research with respect to pilot burnout has emphasized work-related demands such as work overload, as well as job resources such as organizational politics (Kearney, 2008), whereas research linking personal stress, personal resources and pilot burnout is in its infancy.
Research has emphasized the relationship between stress coping strategies and burnout, suggesting that level of burnout was predicted by different coping strategies (Charoensukmongkol, 2013).Proactive coping, which is de ned as oriented coping strategy towards future expectations and challenges (Greenglass et al., 1999), can be regarded as a personal resource to alleviate risk of burnout (Chang & Chan, 2015).Fatigue can serve as subjective personal stress that may be caused by performing multiple cognitive tasks for extended periods under high workload, accompanied with prolonged work hours and natural body-rhythm disturbances (Goffeng et al., 2019).It is noted that fatigue is a main feature and precursor of burnout syndrome, while burnout can be seen as a work-related fatigue condition (Schaufeli & Taris, 2005;Van et al., 2015).Fatigue can account for nearly 21% of human error in aviation accidents and incidents in both military and civil aviation (Harris et al., 2001), such as 1998 Little Rock accident.As mentioned above, a wide range of protective and risk factors for burnout have been identi ed as personal stress and personal resources.In order to evaluate and discriminate personal resources which are invulnerable to burnout and personal stress which is prone to burnout, the present study aimed to examine the robust impact of mindfulness on burnout, and the mediating effects of fatigue and proactive coping.Figure 1 depicted the hypothesized multiple mediation model.

Mindfulness, proactive coping and burnout
It is now well established that mindfulness training has widely used and consistently validated to the reduction of stress/strain in a comprehensive qualitative review (Eby, 2019).Meta-Analysis has evaluate trait mindfulness not only clearly correlated with burnout but also serves as a mitigation tool to treat job burnout (Luken & Sammons, 2016;Mesmer-Magnus et al., 2017;Pennie et al., 2018).It is noted that proactive coping can eliminate and prevent stress before it occurs (Chang & Chan, 2015;Searle & Lee, 2015).Signi cantly positive associations are found between mindfulness and proactive coping in the prediction of life satisfaction (Hinterman et al., 2012).Moreover, regular mindfulness meditation practice contributes indirectly to reduced burnout and higher job satisfaction, in which different coping strategies can differently affect levels of burnout (Charoensukmongkol, 2013).Mindfulness has been considered as a prime characteristic for preventing burnout.As a consequence, it is reasonable to argue that proactive coping has an impact on enhancing one's coping skills to deal with stress, which is consistent with the protective role of mindfulness in stress management.
According to the extended job demand-resource model, coping strategy, regarded as a personal resource, is found to moderate the impact of job demands on burnout.Proactive coping is found to be positively associated with positive outcomes such as engagement, well-being, and negatively associated with burnout (Bermejo-Toro et al., 2015;Searle & Lee, 2015).Study targeted the function of personal resources involved in burnout has indicated that the association between demands and burnout is modulated by proactive coping (Bermejo-Toro et al., 2015).It is suggested that proactive coping produces an effect on burnout and reactions to stress.
Previous research has demonstrated the effect of proactive coping in relation to mindfulness on burnout and health.It is noted that similar protective role of proactive coping is found to moderate relationship between stressors and burnout, as well as relationship between stressors and engagement (Searle & Lee, 2015).In addition, ndings about proactive coping affecting levels of burnout are consistent with the statement that proactive coping ought to be a particularly effective strategy for managing job demands.A stress management intervention provides considerable evidence that proactive coping has a mediating effect in the association between optimism and burnout to promote mental health among nurses (Chang & Chan, 2015).Furthermore, proactive coping mediates the association between emotion appraisal and burnout, in which employees those with higher emotional intelligence can facilitate more proactive coping and then seem to experience symptoms of burnout less frequently than others (Nizielski et al., 2013).As mentioned above, proactive coping has an important role in the association between mindfulness and burnout.

Mindfulness, fatigue and burnout
Fatigue is a consequence of job demands, which can be conceived as a personal stress to result in symptoms of burnout (Aleksandra Basinska et al., 2014).A brief mindfulness-based intervention, which has been validated to cultivate mindfulness and reduce psychological distress, is proved to be effective for increasing mindfulness, and decreasing anxiety, depression, fatigue in workplace (Westphal et al., 2015).Besides, mindfulness practice is more frequently used for clinical application, in which mindfulness-based stress reduction is associated with signi cant improvements in self-reported symptoms of fatigue (Gregoire & Lachance, 2015).Consequently, mindfulness is a signi cant protector for effective prevention from subjective fatigue in reducing stress.
Relationship between burnout and fatigue may be closely intertwined, suggesting an interactional association.However, job-related emotions mediate the relationship between fatigue and burnout among police o cers, in which those individuals low in fatigue may be associated with subsequently reduced burnout (Aleksandra Basinska et al., 2014).Fatigue is some of exhaustion that may recover from adequate rest and sleep, suggesting that fatigue may bring about subsequent burnout.It has demonstrated that a range of benefits from mindfulness-based interventions were found in psychological and physiological outcomes including depression, anxiety, and mental fatigue.In consideration of fatigue can be identi ed in physical realm or mental realm, it is reasonable to suppose that burnout might be a consequence of pilots' fatigue due to longer exposure to ying.
Burnout and fatigue are highly prevalent in a demanding and high-stress environment, especially for safety-related occupations like civil pilots.Measures of burnout can re ect general and mental fatigue; mental fatigue would be primarily related to exhaustion.Research has examined disturbed sleep and fatigue in occupational burnout, high burnout scores are more likely to be associated with self-reported fatigue, and fatigue is regarded to interfere to the onset of emotional exhaustion and depersonalization (Raftopoulos et al., 2012).It is remarkable that low-arousal negative emotions mediate relationship between fatigue and exhaustion (Aleksandra Basinska et al., 2014).Furthermore, reduced fatigue and burnout are found after mindfulness practice, indicating that mindfulness has a similar impact on fatigue and burnout (Gregoire & Lachance, 2015).It can be argued that mindfulness predicts risk for burnout through fatigue.
Proactive coping and fatigue can be factored into the extended job demand-resource model to make it clear that mindfulness exerts its indirect effect on burnout through fatigue and proactive coping.
Research has indicated that mindfulness measures can be utilized for identifying individuals at risk of psychological distress, such as anxiety, depression and burnout (Luken & Sammons, 2016;Westphal et al., 2015).Taking into account the potential risk of pilots' burnout for ight safety, it is signi cant important to ascertain the crucial role of mindfulness on burnout, along with recommendations for prevention and intervention, and to con rm the possible mediating role of fatigue and proactive coping in the preventative effect of mindfulness on burnout.

Participants
Three hundred and nineteen civil pilots were recruited from the China Southern Airlines, ranging from 24 to 49 years of age (M=31.31,SD=6.24), to provide information on individual demographics, mindfulness, fatigue, proactive coping, and burnout.The ight experience of respondents ranged from 860 hours to 48,000 hours (M=14,794, SD=9,573).In order to dispel pilots' misgivings and to enhance the validity of the measurement, respondents were asked to answer the items voluntarily and anonymously, as well as to be informed that their responses would have no effect on evaluation.All methods were carried out in accordance with relevant guidelines and regulations.Informed consent was obtained from all study subjects, and the study design was approved by the appropriate ethics review board of Shaanxi Normal University.

Measures Mindful Attention Awareness Scale (MAAS)
A Chinese translated version of MAAS (Deng et al., 2012), which was originally developed by Brown and Ryan (2003), is a 15-item self-report questionnaire that assesses the degree to which one is attentive to the present moment in one's daily experience.It is rated on a 6-point Likert scale ranging from 1 (almost always) to 6 (almost never).A sample item includes, "I find it difficult to stay focused on what's happening in the present".It has already been validated in the Chinese language to show acceptable reliability (Deng et al., 2012).The coe cient of internal consistency in the current sample was good (α= 0.968).

Proactive Coping Scale (PCS)
The proactive coping scale (subscale of Proactive Coping Inventory) is designed to measure proactive coping (Greenglass et al., 1999).It has been validated and widely used in Chinese context (Gan et al., 2007).An example is "After attaining a goal, I look for another, more challenging one".It comprises 8 questions presented in a 6-point Likert forma, ranging from 1 (not at all true) to 6 (completely true).In this study, the internal consistency was low, with a Cronbach's alpha of 0.947.

The mental Fatigue Scale
The mental fatigue subscale from Fatigue Scale was used to measure the degree of fatigue, which comprises 6 items ranging from 0 (no) to 1 (yes).Questions pertaining to self-reported fatigue evaluate the existence and severity of mental fatigue.Sample item is "Do you have di culty concentrating?"The highest score of fatigue is 6, with a higher score indicating more serious mental fatigue (Chalder et al., 1993).The internal consistency in this study was acceptable, α=0.642.

Maslach Burnout Inventory -General Survey (MBI-GS)
The validated version of the Maslach Burnout Inventory (Maslach et al., 1996) comprises of three subscales which are as follows: emotional exhaustion (EE, 5 items), depersonalization (DP, 4 items) and low personal accomplishment (PA, 6 items), with a high validity and reliability in Chinese context (Wu et al., 2012).Burnout in this study was measured with EE and DP.It includes questions such as "I feel fatigued when I have to get up in the morning to face another day on the job".The items are rated on a 7point Likert-type scale, ranging from 0 (never) to 6 (every day) according to how often the statement is experienced.Hence, high scores in EE and DP scale denote higher degrees of burnout.In the present study, the Cronbach's alpha was 0.964 for entire scale, 0.943 for EE, 0.933 for DP, respectively.

Data Analysis
Descriptive analyses, Pearson correlations among study variables were performed with SPSS 22.0.Structural equation modeling (SEM) was used to test hypothesis model with Mplus 8.3, in which the maximum likelihood estimation method was employed.Measurement model and common method test were validated prior to examining path analyses.In structural equation model, model fit was evaluated using indices such as GFI, NFI, TLI, CFI, RMR, RMSEA, in which GFI, NFI, TLI and CFI greater than .90and SRMR and RMSEA less than .08indicated a good model t."χ 2 /df" was used to assess model t for the reason that statistic was sensitive to sample size, with ratio of less than 3 indicating an acceptable model t.

Descriptive statistics
Descriptive statistics, comparison between groups among observed variables were displayed in Table 1.Items of burnout were coded both as continuous variable for path analysis and categorical variable for descriptive statistics.According to cutoffs suggested by Maslach et al. (1996), which was classi ed with high, intermediate and low levels of burnout, burnout cases were de ned as having a score higher than 75 th percentile on EE and DP.The cutoff point was 3 for EE, 2.75 for DP in the present study, with 25.39% (81) pilots high in EE, 27.90% (89) pilots high in DP.Hence, a total of 98 airline pilots (30.72%) met the defined burnout criteria.In addition, about 32.29% (103) pilots reported one half (3 symptoms) and above symptoms of fatigue.
Mean scores, standard deviations, and Pearson correlations were shown in Table 2.As can be seen, all focal variables were signi cantly correlated.Mindfulness was negatively associated with fatigue, r=-.371, p<.001, and burnout, r=-.832, p<.001, while positively related to proactive coping, r=.839, p<.001.As hypothesized, burnout was positively correlated with fatigue, r=.477, p<.001, whereas inversely related to proactive coping, r=-.815, p<.001.Fatigue was negatively associated with proactive coping, r=-.378, p<.001.In brief, high levels of mindfulness and proactive coping may be associated with low levels of fatigue and burnout among civil pilots.

Measurement model
Con rmatory factor analysis (CFA) test was performed to assess the t of our theorized four-factor model.Reliabilities, Validity and correlations were provided in Table 3. Bootstrapped confidence intervals that do not contain zero signify that an effect is statistically significant.Subsequent interpretation will be made using this criterion.Specifically, the reliabilities reported on the diagonal show strong internal consistency across all measures.The patterns of correlations are consistent with both theory and previous research.The correlation results of variables are as expected.Results indicated that each latent construct produced a good fit to the data.Factor loadings for each latent construct also indicated that the items loaded well onto their respective constructs.
The measurement model comprised of four latent constructs.All loadings of item on their constructs were statistically signi cant at p < 0.001 and over 0.426.Especially, 95% bias-corrected bootstrap CIs for the relative indirect effects that do not straddle zero, indicating that mindfulness indirectly influence burnout through fatigue and proactive coping.This supports a claim that fatigue and proactive coping as mediators of the effect of mindfulness on burnout.The overall t of the measurement model was good, and these indices were acceptable, χ 2 = 941.329,df = 659, χ 2 /df = 1.428,TLI = .939,CFI = .943,SRMR = .045,RMSEA = .037.Given the acceptable results in the measurement model, the path model was tested to examine the associations among the latent variables.
Common Method Variance should be tested because all data were based on self-report.A single factor approach of Harman was carried out to check the results for common method bias, from which we can assess quality of the measurement model.We added one method factor that loaded on all indicators on the basis of measurement model, to examine the hypothesis testing "single factor explaining all variations".The model did not converge.Then we tested an alternative model which allowed all indicators to load on one single factor rather than loaded on the four latent factors.Results showed that compared to original model, this model had signi cantly worse model t χ 2 = 1996.582,df = 665, χ 2 /df = 3.002, TLI = .717,CFI = .732,SRMR = .068,RMSEA = .079.As a consequence, it was suggested that the observed relationships among focal variables should not be solely attributed to common method variance.

Structural Equation Model
In order to examine multiple mediation effects simultaneously, the direct, indirect, and total effects including bias-corrected bootstrapped con dence intervals for mediation effects were assessed in Structural equation modeling (SEM).Tables 4 display parameter estimates and pairwise contrasts for specific indirect effects.The structural model provides a good t to the data.Significant specific indirect effects were found in models transmitting the effects of mindfulness on burnout, with further modelling suggesting these effects could be qualified with reference to fatigue and proactive coping.The effects of mindfulness on burnout through fatigue and proactive coping were examined.The path model has suggested that mindfulness exerts an effect on burnout via fatigue and proactive coping, χ 2 = 940.495,df = 660, χ 2 /df = 1.425,TLI = .940,CFI = .944,SRMR = .045,RMSEA = .037.
To test whether fatigue and proactive coping mediated associations between mindfulness and burnout.The association between mindfulness and burnout were signi cantly related to two mediators: fatigue (β = -.074,95%CI = -.106 to -.036) and proactive coping (β = -.842,95%CI = -1.215 to -.635).The indirect effects through the other two mediators are signi cant.The direct effect of mindfulness on burnout was not signi cant (β = -.096,95%CI = -.346 to .263).The indirect effects of mindfulness on burnout through fatigue and proactive coping were evaluated in proposed structural relationships among study variables.On the basis of the results, it could be concluded that fatigue and proactive coping fully mediated the association between mindfulness and burnout.
Bootstrapping indirect effects and 95% con dence intervals for multiple mediation model were conducted to compare mediating roles of fatigue and proactive coping.Bootstrapping analyses indicated that mindfulness was determined to have an indirect effect on burnout, in which fatigue and proactive coping mediated the effect of mindfulness on burnout.Using percentile bootstrap and bias-corrected bootstrapping procedures to evaluate mediating effects, results indicated that indirect effect which was mediated by proactive coping had more power than those of fatigue (indirect effect of proactive coping minus indirect effect of fatigue = -.768,95%CI = -1.211 to -.631).As described in Table 4, ndings supported that the mediating role of proactive coping was signi cantly larger than fatigue.

Discussion
Consistent with prior research, the current study addressed a moderate level of burnout among Chinese civil pilots (Fanjoy et al., 2010).Contrary to the nding that single nurses experienced more emotionally exhausted than married nurses (Sahraian et al., 2008), our results showed that married pilots suffered from higher levels of burnout than single pilots.As with a nurse, a pilot must encounter the same scheduling problems as well as the enormous work pressure that demands substantial responsibility in a challenging environment.Perhaps the opposite conclusion is probably attributed, at least in part, to the argument that the biggest difference between nurses and pilots is not the nature of the work, but the discrepancy between one being a female-dominated profession and the other a male-dominated profession.Another plausible alternative explanation could be that married pilots may face more complicated non-work related pressure or work-family con icts than others.It may also be partly due to the fact that some of the pilots may spend a fair amount of time away from home as part of their ight schedule.
Burnout, regarded as a risk factor for occupational health, is a major determinant of job dissatisfaction and turnover intention among pilots (Ceyhun & Ozbag, 2014;Fanjoy et al., 2010).Exhaustion was a strong predictor that can help inform performance improvement and risk mitigation for safety among Air Force Drone Operators (Chappelle et al., 2014).Results showed that mindfulness played an important part in relieving and preventing burnout.Whereas research has examined how job demands and job resources relate to burnout among ight crewmembers and pilots (Kearney, 2008), there is surprisingly little study on how personal stress and personal resources are related to burnout.In order to ensure ight safety and economic effectiveness, it is far more important for researchers to ascertain and distinguish risk and protective factors in burnout prevention among pilots.For identifying personal stress and personal resources in burnout prevention, the present study examined the robust protective effect of mindfulness on burnout, and the indirect effect of mindfulness on burnout through causally linked multiple mediators of fatigue and proactive coping.
Consistent with previous ndings suggesting that mindfulness acts as a buffer against burnout (Taylor & Millear, 2016), the current study demonstrated the protective effect of mindfulness on burnout among civil pilots.Mindfulness had a positive effect on pilot burnout, corroborating prior ndings that mindfulness training has been consistently validated to moderate the adverse effects of job-related stress on burnout (dos Santos et al., 2016;Luken & Sammons, 2016).Consistent with previous studies suggesting that mindfulness made a strong contribution to protecting against the onset of burnout (Luken & Sammons, 2016;Taylor & Millear, 2016), the current study revealed the protective effect of trait mindfulness on burnout.
Prior research has indicated that proactive coping mediated the relationship between stress and engagement, suggesting protective roles in stress management for these purposeful coping approaches (Gan et al., 2007).The results indicated that mindfulness had an impact on proactive coping and burnout, suggesting that mindfulness had a positive effect on coping strategy (Charoensukmongkol, 2013).As predicted, proactive coping were signi cantly associated with burnout, in which it facilitated adaptive regulation of potential challenges in helping one to be insusceptible to burnout.Similar to previous research nding that coping strategies mediate positive effects of mindfulness on burnout (Charoensukmongkol, 2013), the present study addressed the mediating role of proactive coping in the association between mindfulness and burnout.The robust relationship of higher levels of proactive coping with lower levels of burnout is mainly due to the fact that coping strategies facilitate positive outcomes and protect against the risk of burnout symptoms (Searle & Lee, 2015).Our work has extended previous research to ascertain the important role of mindfulness and proactive coping in protecting against burnout among pilots.
According to the nature of airline transportation, the occupational stress-related phenomenon that pilots may be more prone to suffer from sleep deprivation, fatigue and burnout.Research regarding Mindfulness-based intervention demonstrated the availability and good e cacy of mindfulness training for reducing symptoms of fatigue and burnout (Luken & Sammons, 2016;Westphal et al., 2015).Furthermore, The current study con rmed that fatigue mediated the effect of mindfulness on burnout, which was consistent with previous studies suggesting that individuals low in fatigue may be associated with subsequently reduced burnout (Aleksandra Basinska et al., 2014).In view of the great signi cance of fatigue and burnout on ight performance, our ndings contribute to the argument that mindfulness is crucial for pilots to protect against fatigue and burnout.Mindfulness made a contribution to protect against the onset of burnout and fatigue.Thus, our ndings highlighted the value of mindfulness, and potential bene ts of mindfulness in diminishing fatigue and subsequent burnout.
Theoretical Implications in Job Model current attempted to con rm the in uential role of personal stress and personal resources in burnout, by conducting a correctional cross-sectional study to assess the relationships between mindfulness, fatigue, proactive coping, and burnout among pilots.According to the extended job demand-resource model (Pennie et al., 2018), personal resources act as positive self-evaluations to moderate effects of job demands, and to predict performance, job satisfaction, and burnout (Chang & Chan, 2015;Charoensukmongkol, 2013).Therefore, personal factors can help explain why certain individuals suffer from burnout or why certain individuals have more symptoms of burnout than others (Searle & Lee, 2015).Though enormous studies concerned about the roles of work-related characteristics and resources on burnout, our results con rmed the possible mechanism that mindfulness had an important preventative effect on burnout, in which the effect was probably triggered by personal resources to exert effect to buffer against stress.It is suggested that coping strategy, regarded as a valued resource, may help individuals take appropriate actions to anticipate and deal with potential challenges (Bermejo-Toro et al., 2015;Searle & Lee, 2015).In hence, it seems that individuals engaged in proactive coping to offset potential problems may be less vulnerable to burnout as a result of the fact that proactive coping integrates a positive approach of self-regulatory goal attainment to buffer against demands and stress to burnout (Bermejo-Toro et al., 2015;Charoensukmongkol, 2013;Searle & Lee, 2015).However, the robust effect of mindfulness in reducing burnout was rapidly decreased, when taking into account the mediating roles of fatigue and proactive coping.The results made a contribution to the extended job demand-resource model that proactive coping acts as a personal resource to play a protective role in preventing burnout, while fatigue was regarded as personal stress to have an adverse effect on burnout.The results were also consistent with previous research with regard to the effectiveness of mindfulness training practice and fatigue reduction program.
Practical Implications for mindfulness intervention and burnout reduction the fact that the approach to train an excellent civil pilot usually di cult, expensive, and time-consuming, it is extremely important to select the most suitable candidate and then train them well to ensure ight safety.The nature of the ight profession and high demand for safety may bring about high job stress, forcing pilots to withdraw psychologically with tremendous pressure, ine ciency, low organizational commitment, and risk of ight accidents.The current study has extended previous research suggesting that mindfulness, which protects against experiencing the negative effects of stress, helps to increase resistance to pilot burnout.We also found a mediating role of fatigue and proactive coping in the indirect effect of mindfulness on burnout.The results were undoubtedly consistent with previous in which mindfulness was attested to have a bene cial role not only in promoting wellbeing, but also in decreasing anxiety, depression, and burnout (Charoensukmongkol, 2013;dos Santos et al., 2016;Westphal et al., 2015).Additionally, the 4-month Mindfulness training has been validated to cultivate trait mindfulness in Military Helicopter personnel, as measured by FFMQ (Meland, Ishimatsu, et al., 2015).Our ndings highlighted the value of personal resources, and the potential practical bene ts of utilizing mindfulness measures in pilot training programs for identifying pilots at risk of burnout.
Mindfulness practice is frequently used for practical applications.Mindfulness-based stress reduction is associated with a signi cant decrease in burnout rates (Luken & Sammons, 2016).As previously mentioned, mindfulness interventions elevate proactive coping and reduce fatigue, thus making employees less likely to experience burnout.It is not surprising then that mindfulness training combined with proactive coping can exert major protective effects on the occurrence and development of burnout.The current study bridged the research gap that could have implications for burnout prevention, making a thorough inquiry about the mechanism of how mindfulness can affect burnout.When considering stress management training in practice, the signi cant roles of proactive coping to modulate the effect of mindfulness on burnout among pilots should not be neglected.
The current study give important insight into how future fatigue and burnout prevention can be more targeted.It may have particular applied implications as training to improve the level of mindfulness has previously been shown to have stress-reducing effects in aviators, while the mechanisms behind the effects is less known.The current study extended previous research to suggest that mindfulness, which played a predictive role to modulate negative effect of stress, would help to increase resistance to pilots' fatigue and burnout.We demonstrated the robust role of mindfulness in burnout reduction, and also assessed the mediating role of fatigue and proactive coping in the indirect effect of mindfulness on burnout.The results were undoubtedly consistent with previous research that mindfulness was attested to have a bene cial role not only in promoting well-being but also in decreasing anxiety, depression and burnout (Westphal et al., 2015).Additionally, it is also well noted that mindfulness practice is the most widely used intervention to mitigate negative effects of stress on fatigue (Gregoire & Lachance, 2015).As previously mentioned, mindfulness intervention can not only reduce fatigue but also elevate proactive coping, thus make employees less likely to experience burnout.It is not surprising then that mindfulness training combined with proactive coping can exert major protective effects on the occurrence and development of burnout.Considering combined roles of fatigue and proactive coping, mindfulness indirectly affected burnout through two mediators without direct effect on burnout.It may have particular applied implications as training to improve the level of mindfulness has previously been shown to have stress-reducing effects in aviators.The current study bridged research gap that could have implications for burnout prevention and Fatigue Risk Management System (FRMS), making a thorough inquiry about mechanism of how does mindfulness work in fatigue and burnout reduction.

Limitations and Directions for Future Research
The present study has several limitations that require mentioning.Firstly, correlation coe cients among the study variables were extremely high.This may be partially attributed to socially desirable responding and faking, a relatively small homogeneous sample, and inappropriate measurement instruments.
Secondly, self-report measures have the potential for multicollinearity issues and observational error.Especially, fatigue/sleepiness has clearly been demonstrated to have a number of cognitive effects that may in uence performance and lead to accidents.Further research with respect to pilot fatigue can focus around fatigue and sleepiness, which is typically measured with Samn-Perelli Crew Status Check (Caldwell & Caldwell, 2004) and Karolinska Sleepiness Scale (Wu et al., 2016).Furthermore, due to the various limitations such as the research sample, sample size, and cross-sectional design, caution is needed with regard to generalizability of the ndings.We cannot draw conclusions about causality from the correlation data based on a cross-sectional survey.In addition, research has demonstrated that fatigue/sleepiness have a number of cognitive effects that may in uence performance and lead to accidents.Further data are needed to draw inferences concerning the relationship with aviation accidents.More objective measures or instruments should be used or developed to better assess the negative factors that are particularly associated with accident proneness, self-perceived poor performance, and unhealthy mental conditions among pilots.Additionally, longitudinal studies that can better explore and ascertain evidence of causal relationships rather than cross-sectional correlations should be conducted.More importantly, practical research should be performed to further investigate causation among positive psychological factors, mental health, job performance, and safety behaviors in the aviation domain.

Figures
Figure 1 A multiple mediation model for the association between mindfulness and burnout.

Table 4
Comparison of Specific Indirect Effect.