Machiavellianism And Quality Of Life:the Exploration Of Boundary Condition And Internal Mechanism

The influence of personality on physical and mental health has been well-documented.As a personality trait,Machiavellianism(MACH for short)has repeatedly been proved to have a significant negative impact on physical and mental health.However,the mechanism by which MACH affects physical and mental health is still unclear.Therefore,this study focused on the relationship between MACH and quality of life(QOL for short)and aimed to explore boundary conditions of this relation and to certify potential mechanism under this link.First of all,gender and age are common risk factors for many diseases and have important effects on an individual's QOL.Meanwhile,there are differences in the level of MACH among different gender and age groups.Besides,the World Health Organization pointed out that lifestyle factors have surpassed genetic and medical factors to become the primary factors affecting health.And most health behavior models and health studies regard healthy lifestyle as an intermediary between personality and health outcomes.Therefore,this study considers lifestyle as a mediational variable between MACH and QOL.Additionally,social support has been found to be closely related to personality,lifestyle and QOL,which may buffer the impact of personality on lifestyle and health.Therefore,this study assumed that social support might play a moderating role in the above mediation model.This study aims to verify the mediating and mediating effects of gender and age on MACH and QOL,as well as the mediating role of lifestyle and moderating role of social support on the link between MACH and QOL through three sub-studies.Study 1: Through a large sample survey,this research aimed to reveal the status quo of MACH and QOL among Chinese students,and to investigate the role of gender and age in moderating the relationship between MACH and QOL.6,258 primary and middle school students and 1,161 college students were recruited to explore the gender and age distribution characteristics of MACH and QOL.Primary and middle school students were investigated adopting Kiddie Machiavellianism Scale(KMS)and Pediatric Quality of Life Inventory Version 4.0(Peds QLi4.0).College students were surveyed using Machiavellianism personality scale(MPS)and 36-Item Form Health Survey(SF-36).The result showed that in both primary and secondary school students and college students,the scores of MACH in male students were significantly higher than that of female students.Among primary and secondary school students,the QOL in male students was significantly better than that of female students,while in college students,the QOL in male students was significantly worse than that of female students.In both primary and secondary school students and college students,the score of MACH increased with age while the QOL decreased with age.In both two samples,MACH was significantly negatively correlated with QOL.Gender moderated the relationship between MACH and QOL among primary and secondary school students and college students,while age only moderated the relationship between MACH and QOL among primary and secondary school students.Study 2: To deeply explore the internal mechanism of MACH's influence on QOL,that is,to explore the mediating role of lifestyle between the MACH and QOL,as well as the moderating role of social support on the hypothesized mediating model.1,161 college students were surveyed using Machiavellianism personality scale(MPS),Healthy Lifestyle Scale for College Students,36-Item Form Health Survey(SF-36)and Perceived Social Support Scale(PSSS).The result showed that MACH was significantly negatively correlated with lifestyle(r=-0.29,p<0.01),social support(r=-0.24,p<0.01)and QOL(r=-0.30,p<0.01),lifestyle(r=0.44,p<0.01)and social support(r=0.38,p<0.01)were positively correlated with QOL.Lifestyle was also positively correlated with social support(r=0.32,p<0.01).MACH affected QOL indirectly through lifestyle(?=-0.14,p<0.05,95%CI[-0.21,-0.08]).Social support moderated the relationship between MACH and lifestyle.Study 3: Longitudinal research design was adopted to verify the causal relationship between MACH,lifestyle,social support and QOL.A total of 373 college students were selected to participate in the 10-months longitudinal study.Measures were the same as measures in study 2.After controlling T1 QOL,T1 MACH had a significant predictive effect on T2 QOL(?=-0.20,p<0.01,95%CI[-0.32,-0.11]).T1 MACH either directly affected T2 QOL(?=-0.13,p<0.05,95%CI[-0.23,-0.03])or indirectly affected T2 QOL through T1 lifestyle(?=-0.07,p<0.05,95%CI[-0.12,-0.04]).T1 MACH either directly affected T2 QOL(?=-0.13,p<0.05,95%CI[-0.22,-0.04])or indirectly affected T2 QOL through T2 lifestyle(?=-0.06,p<0.05,95%CI[-0.12,-0.01]).T1 MACH either directly affected T2 QOL(?=-0.13,p<0.05,95%CI[-0.23,-0.03])or indirectly affected T2 QOL through T1 lifestyle(?=-0.07,p<0.05,95%CI[-0.12,-0.04]).T1 MACH either directly affected T2 QOL(?=-0.13,p<0.05,95%CI[-0.22,-0.04])or indirectly affected T2 QOL through T2 lifestyle(?=-0.06,p<0.05,95%CI[-0.12,-0.01]).Social support moderated the relationship between T1 MACH and T1 lifestyle.Conclusion:(1)Among Chinese students,MACH is negatively correlated with QOL,and MACH is an antecedent variable of poor QOL.(2)MACH and QOL are different between gender and age groups,and gender as well as age can moderate the relationship between MACH and QOL.(3)Lifestyle plays a mediating role between MACH and QOL,that is,MACH affects QOL through lifestyle.(4)To some extent,social support can buffer the negative impact of MACH on lifestyle.