Table 2.

Adjustment values for the tested models.

	Χ2 S-B	df	p	CFI	NFI	NNFI	RMSEA	90% CI of RMSEA	Δ χ2 S-B
Model 1	689.64	77	< 0.001	0.73	0.71	0.68	0.19	0.18–0.21	–
Model 2	325.08	76	< 0.001	0.89	0.86	0.87	0.12	0.11–0.14	− 4154.12
Model 3	264.02	74	< 0.001	0.92	0.89	0.90	0.11	0.10–0.12	63.88***
Model 4	138.85	71	< 0.001	0.97	0.94	0.96	0.07	0.05–0.08	98.76***

Model 1: A single-factor structure; Model 2: Two-factor structure (leadership styles factor and energy factor); Model 3: Three-factor structure (leadership styles, vigor at work and engagement); Model 4: Four-factor structure (TFL, AL, vigor at work and engagement).

CFI = Comparative fit index; df = Degrees of freedom; CI = Confidence interval; NFI = Normed fit index; NNFI = Non-normed fit index; RMSEA = Root mean square error of approximation; χ² S-B = Satorra–Bentler chi-square; Δ χ² S-B = Scaled Satorra–Bentler chi-square difference.

***p < 0.001.