Table 2.
Unconditional latent growth curves parameters estimates for global cognitive score changes using linear, free, and quadratic time parametrizations and models fit indices. Weighted estimates are for U.S. community-dwelling adults (65-years or older) from the Health and Retirement Study (1998–2010).
| Linear Model |
Free Functional Form |
Quadratic Model |
|
|---|---|---|---|
|
|
|||
| Estimates | Estimates | Estimates | |
|
|
|||
| Growth Parameters | |||
| Fixed Effects | |||
| Intercept | 22.64 | 22.59 | 22.50 |
| Slope | −0.84 | −0.79 | −0.61 |
| Quadratic | -- | -- | −0.04 |
| Random Effects | |||
| Intercept | 13.69 | 13.55 | 14.17 |
| Slope | 0.45 | 0.38 | 1.92 |
| Quadratic | -- | -- | 0.04 |
| Model fit | |||
| Chi-Square (df) | 431.442 (23) |
336.554 (18) |
171.924 (19) |
| Scaling Correction Factor | 1.234 | 1.177 | 1.248 |
| AIC | 227571 | 227445 | 227262 |
| BIC | 227656 | 227566 | 227375 |
| Sample-Size Adjusted BIC | 227618 | 227511 | 227324 |
| RMSEA | 0.045 | 0.045 | 0.030 |
| CFI | 0.976 | 0.981 | 0.991 |
| TLI | 0.978 | 0.978 | 0.990 |
| SRMR | 0.036 | 0.062 | 0.023 |
Note 1: AIC=Akaike Information Criteria; BIC= Bayesian Information Criteria; RMSEA=Root Mean Square Error of Approximation; CFI=Comparative Fit Index; TLI=Tucker Lewis Index; SRMR= Standardized Root Mean Square Residual.