Comparing the psychometric evidence of the Depression, Anxiety, and Stress Scale-21 (DASS-21) between Spanish and Chinese primary schoolteachers: insights from classical test theory and Rasch analysis

Table 4 Results of CFA model fit

	χ² (df)	CFI	NNFI	RMSEA; 90% CI	SRMR
Spain
One-factor structure	548.29 (189)	0.991	0.991	0.038; 0.034–0.041	0.055
Two-factor structure	468.11(188)	0.993	0.993	0.033; 0.029–0.037	0.050
Three-factor structure	342.64 (186)	0.996	0.996	0.025; 0.021–0.029	0.043
Bifactor model	205.65 (168)	0.999	0.999	0.013; 0.005–0.019	0.033
China
One-factor structure	519.96 (189)	0.996	0.995	0.026; 0.023–0.029	0.045
Two-factor structure	516.36 (188)	0.996	0.995	0.026; 0.023–0.029	0.045
Three-factor structure	514.34 (186)	0.996	0.995	0.026; 0.023–0.029	0.044
Bifactor model	435.44 (168)	0.997	0.996	0.025; 0.022–0.028	0.040

CFI = comparative fit index; NNFI = non-normed fit index; RMSEA = root mean square error of approximation; SRMR = standardized root mean square residual; CI = confidence interval

ISSN: 2050-7283