Table 2. Goodness of fit indices for the hypothetical models tested and measurement invariance across gender and age.
| Model | χ2 | df | CFI | TLI | RMSEA (CI 90%) | WRMR | ΔCFI |
|---|---|---|---|---|---|---|---|
| 1 factor | 620.50 | 35 | .95 | .94 | .07 (.07-.08) | 2.27 | |
| 1 factor + CE* | 513.89 | 32 | .96 | .95 | .07 (.06-.07) | 2.01 | |
| Measurement Invariance for the one factor model | |||||||
| Gender | |||||||
| Male (n = 1287) | 319.87 | 35 | .95 | .93 | .08 (.07-.09) | 1.62 | |
| Female (n = 1627) | 369.26 | 35 | .96 | .94 | .08 (.07-.08) | 1.73 | |
| Configural invariance | 638.74 | 73 | .96 | .95 | .07 (.07-.08) | 2.35 | |
| Strong invariance | 778.85 | 89 | .95 | .94 | .07 (.07-.08) | 2.75 | -.01 |
| Age | |||||||
| 13–15 years old (n = 1265) | 293.53 | 35 | .95 | .94 | .08 (.07-.09) | 1.55 | |
| 16–19 years old (n = 1649) | 353.01 | 35 | .96 | .94 | .07 (.07-.08) | 1.71 | |
| Configural invariance | 643.49 | 73 | .95 | .94 | .07 (.07-.08) | 2.35 | |
| Strong invariance | 692.02 | 89 | .95 | .95 | .07 (.07-.08) | 2.54 | -.01 |
Note. CE = Correlated Errors; χ2 = Chi square; df = degrees of freedom; CFI = Comparative Fit Index; TLI = Tucker-Lewis Index; RMSEA = Root Mean Square Error of Approximation; CI = Confidence Interval; WRMR = Weighted Root Mean Square Residual; ΔCFI = Change in Comparative Fix Index.
*CE = 3 with 6; 3 with 7; 19 with 20.