ABSTRACT
Objective:To test the validity and reliability of the General Alienation Scale (GAS)in college students sample.Methods:Totally 1200 college students were surveyed,using classical test theory (CTT)and i-tem response theory (IRT)to test the psychometric properties of GAS.Under the framework of CTT,item selec-tion was performed with all data.Then,the sample was divided into two groups based on the input order to exam-ine the construct validity.Exploratory factor analysis (EFA)and parallel analysis (PA)were performed with odd group,while confirmatory factor analysis (CFA)was performed with even group.Criterion validity was examined with the short-form of the University of California Los Angeles Loneliness Scale (ULS-8),General Self-Efficacy Scale (GSES),Rosenberg Self-Esteem Scale (RSES).Under the framework of IRT,all data was fitted the rat-ing scale model (RSM),including the principal component analysis of residuals (PCAR),the item fit indexes (Infit and Outfit),measurement reliability (item separation index,item reliability,person separation index and person reliability)and the Wright map.Results:Under the framework of CTT,the GAS was retained 13 items except item 2 and 5.The results of both EFA and PA showed that 13 items of GAS was one-dimensional,and there was a good fit of CFA (χ2 /df=2.689,P scores respectively (Ps <0.001 ).The Cronbach 's αcoefficient and confidence interval were 0.81 (0.80, 0.83).Under the framework of IRT,the ratio of first-paired eigenvalue was 1.6 in PCAR.The infit and outfit of retaining 13 items in CTT were from 0.6 to 1.4 excluding item 4.The item separation index,item reliability,per-son separation index and person reliability of the 12-item GAS were10.91,0.99,2.14 and 0.82 respectively.The item difficulty can matched with person ability,and they were closed to the normal distribution.Conclusion:It suggests that the General Alienation Scale (GAS)is of good validity and reliability,and it could be used as an ef-fective tool for measuring the alienation of college students.