Table 1. Fits of the main SEMs tested.
Model | χ2 | df | RMSEA | CFI | SB | AIC |
---|---|---|---|---|---|---|
Single-factor (A), e.g., Berry et al.37 | 645 | 27 | 0.270 | 0.722 | 1.080 | 2838 |
Two-factor (B), e.g., Squire38 | 424 | 26 | 0.220 | 0.821 | 1.032 | 2580 |
Two-factor (C), e.g., Gardiner et al.39 | 340 | 26 | 0.196 | 0.859 | 1.001 | 2483 |
Two-factor (D), e.g., Yonelinas24 | 324 | 23 | 0.211 | 0.855 | 0.940 | 2472 |
Three-factor (E) | 78 | 24 | 0.084 | 0.976 | 0.946 | 2220 |
Three Factor with Age | 80 | 30 | 0.072 | 0.980 | 0.946 | 2928 |
Three Factor with Age & Edu | 94 | 36 | 0.071 | 0.977 | 0.953 | 3778 |
Three Factor with Age, Edu & gF | 214 | 78 | 0.074 | 0.957 | 0.977 | 6725 |
Three Factor with GM and WM ROIs* | 118 | 72 | 0.046 | 0.981 | 0.982 | 7815 |
Three Factor with GM constrained* | 142 | 78 | 0.052 | 0.974 | 0.983 | 7828 |
Three Factor with WM constrained* | 135 | 78 | 0.049 | 0.977 | 0.984 | 7821 |
Three Factor with GM, WM and Age* | 139 | 85 | 0.046 | 0.979 | 0.980 | 8282 |
Three Factor with WM, Age, GM-nulled* | 159 | 94 | 0.048 | 0.974 | 0.979 | 8283 |
Three Factor with GM, Age, WM-nulled* | 149 | 94 | 0.044 | 0.972 | 0.985 | 8273 |
The SEMs are grouped according to those fitting the same data (same observed variables), since one cannot compare all model fit indices across fits to different data. Edu = Education Level; gF = Fluid Intelligence; GM = Gray Matter (Volume); WM = White Matter (Index). For fit measures, see Methods (df = degrees of freedom left in data). *=These models additionally contained Education and TIV (affecting all memory factors). Note that the χ2 reported is the Satorra-Bentler scaled χ2, with the scaling factor reported as SB.