Structural Equation Modeling And Its Application In Medical Research

Structural equation modeling (SEM) has been developed as one of theorysystems of latent variable modeling since 1970's．It conquers the shortcomingsof traditional statistical methods such as multiple regression,path analysis andfactor analysis．At the same time,SEM has formed it's own unique advantageson the basis of succeeding to these methods' virtues．In summary,(1) SEM candeal with not only the relationships of manifest variable and latent variable butalso the ones of latent variables．(2) SEM can estimate measurement error aswell as other parameters．(3) SEM analysis data by the means of confirmatorybut not exploratory． The change of medicine pattern leads to complexes of the cause ofdiseases,which requires the improvement of statistical methods．SEM do adaptthis．So,it is significant to inducing SEM in medical research． In my paper,the principle and method of SEM are introduced,especiallythe goodness of fit index used to evaluate model's fitness are expounded．Theseindex are classified absolute fit indices,relative fit indices,indices ofinformation criteria and penalty fit indices．The advantage and disadvantage ofthese indices are also explored．Of these indices,NNFI,CFI,AGFI and RMSEAare excellent．In example analysis,a random sample made up of 318 medicalworkers in certain hospital was surveyed using occupational stress inventoryrevised edition (OSI-R)． Structural equation modeling between occupationtask and occupation stress as well as the one between individual coping styleand occupation stress are constructed．The construct validity of OSI-R isanalyzed applying confirmatory factor analysis (CFA)．The results show:allthree of questionnaire ORQ , PSQ and PRQ have good validity ． Roleambiguity(RA),role boundary(RB) and vocational strain(VS),RA,physicalenvironment(PE)and psychological strain(PSY) , RA and interpersonal IIIstrain(IS),PE and physical strain(PHS) have positive relations,while socialsupport(SS) and VS,rational coping(RC),recreation(RE) and PSY,RC and IS,RE and PHS have negative relations． The theory of equivalent model is explored,advice on how to use correctlycorrelation matrix to fit model is given in discussion．...