TABLE 4.

Model fitting indicators for confirmatory and bifactor MIRT models.

Model fit indicators	5-factor CFA (first-order)	Bifactor MIRT
CFI	0.898	0.943
TLI	0.820	0.923
SRMSR	0.037	0.036
RMSEA	0.024	0.023
M2	938.79	777.57
Akaike information criterion	20184.16	19699.01
Bayesian information criterion	20673.06	20328.65
Sample adjusted BIC	20254.44	19789.51
Log-likelihood (LL)	-9960.082	-9679.505

Δ X² (38) = 561.154, p < 0.001.