We estimated models with linear and quadratic slopes. Model fit was assessed using the following indices: the comparative fit index (CFI), the Tucker–Lewis index (TLI), and the root-mean-square error of approximation (RMSEA). Although no single set of threshold values for these statistics can be relied upon in isolation, we favored models that exceeded 0.95 for TLI and CFI, although a CFI > 0.90 is sometimes considered acceptable (Bentler, 1990, 1992; Tucker & Lewis, 1973), as are models with an RMSEA below 0.05 (Steiger, 1990).
