Table 5.

Multigroup confirmatory factor analysis for age and gender subgroups

Invariance steps	Gender	RMSEA	TLI	CFI	ΔCFI	Age	RMSEA	TLI	CFI	ΔCFI
Configural invariance	Female	0.051	0.934	0.950		Older adults	0.040	0.960	0.970
	Male	0.051	0.934	0.950		Young adults	0.040	0.960	0.970
Metric invariance	Female	0.052	0.932	0.943	0.007	Older adults	0.042	0.957	0.964	0.006
	Male	0.052	0.932	0.943	0.007	Young adults	0.042	0.957	0.964	0.006
Scalar invariance	Female	0.050	0.936	0.943	0.000	Older adults	0.041	0.959	0.963	0.001
	Male	0.050	0.936	0.943	0.000	Young adults	0.041	0.959	0.963	0.001
Strict invariance	Female	0.048	0.941	0.942	0.001	Older adults	0.041	0.959	0.960	0.003
	Male	0.048	0.941	0.942	0.001	Young adults	0.041	0.959	0.960	0.003

Criteria for an acceptable fit were a RMSEA of <0.06, and a CFI, and a TLI of ≥0.90. Configural invariance—no constraints; Full metric invariance—with all factor loadings constrained equal. Scalar invariance—with all intercepts constrained equal; Strict invariance—with all factor loadings and intercepts fixed; Measurement invariance is assumed when ΔCFI is ≤0.01.

CFI, Comparative Fit Index; RMSEA, root mean square error of approximation; TLI, Tucker-Lewis Index.