LCGA was performed on all three parenting dimensions conjointly. Intercepts and slopes were modelled using 12 indicators (assessments). Factor loadings of the intercept on all indicators were set to 1, loadings of the linear slope were set to 0, 1, 2, 3, etc., and loadings of the quadratic slope were set to equal the square of the linear loadings (0, 1, 4, 9, etc.). Several criteria were used to decide on the number of classes. The Bayesian Information Criterion (BIC) for a solution with
k classes should be lower than for a solution with
k-1 classes. Classification accuracy was assessed by entropy (
E), ranging from 0.00 to 1.00, with higher values indicating more accurate classification. The bootstrap Lo-Mendell-Rubin Test (BLRT;
Nylund, Asparouhov, & Muthén, 2007) provides a
p-value to indicate if there is a statistically significant improvement in fit through including an additional class. Finally, we evaluated the practical usefulness of the classes. As expected, LCGA favoured a 4-class solution (BIC = 22947.52;
E = .86) over a 2-class (BIC = 25201.61;
E = .89) and 3-class solution (BIC = 23871.56;
E = .87), with BLRT accompanying the 4-class solution significant at
p < .001. In the 5-class solution (BIC = 22124.75;
E = .87), some classes were variations on a single theme, hence our choice for the more parsimonious 4-class solution. presents intercepts and slopes for this solution.
| Table 1Parameter Estimates of Parenting Trajectory Classes Across Grades 1–12 |
Class 1 (N = 197) was labelled indulgent parenting, characterized by moderate monitoring during childhood (with steep decreases during adolescence), high positive parenting (with decreases across time), and high inconsistent discipline (with increases across time). Class 2 (N = 175) was labelled uninvolved parenting, characterized by low monitoring (with decreases across time), low positive parenting (with decreases across time), and high stable inconsistent discipline. Class 3 (N = 304) was labelled authoritarian parenting, characterized by high monitoring (with decreases during adolescence), low positive parenting (with decreases across time), and low stable inconsistent discipline. Class 4 (N = 375) was labelled authoritative parenting, characterized by high monitoring (with increases in childhood and decreases in adolescence), high positive parenting (with slight decreases across time), and low stable inconsistent discipline. Boys and girls were evenly distributed among these classes (χ2(3) = 6.83, ns). gives an overview of the model-estimated mean values for these four classes. Panel A displays monitoring scores, Panel B positive parenting scores, and Panel C inconsistent discipline scores.
Next, multigroup latent growth curve modeling was conducted to investigate whether children of these classes developed differently (
Duncan, Duncan, Strycker, Li, & Alpert, 1999). All models included a significant quadratic slope, except for alcohol use and antisocial behavior. First, a fully unconstrained baseline model was estimated with all growth parameters being freely estimated in all four classes. Second, intercepts were held equal among all classes, followed by a model in which slopes were held equal. Third, if these constrained models provided a worse fit to the data than the baseline model (indicating that the respective growth parameters could not be considered as equal in all four classes), subsequent multigroup models were estimated in which intercepts and slopes were set free again in certain classes. gives an overview of all final parameter estimates. presents final multigroup models for alcohol use (Panel A), cigarette use (Panel B), antisocial behavior (Panel C), and internalizing symptoms (Panel D). For alcohol use and internalizing symptoms, ancillary multigroup analyses demonstrated that intercepts and slopes could be fixed as equal between boys and girls in all four classes meaning that no substantial gender differences emerged for these two variables.
| Table 2Final Multigroup Parameter Estimates of Outcome Variables in the Four Parenting Trajectory Classes |
For alcohol use, the multigroup model demonstrated that the intercept (with a value of 0.174 in ) could be held equal in all four classes (χ2(85) = 195.47; RMSEA = .07; CFI = .95) because this was not accompanied by a decrease in fit (Δχ2(3) = 2.43, p = .49) as compared to the less parsimonious baseline model (χ2(82) = 193.04; RMSEA = .07; CFI = .95). Next, the linear slope could not be held equal in all classes (χ2(85) = 230.50; RMSEA = .08; CFI = .93) as this resulted in a significant decrease in fit (Δχ2(3) = 37,46, p < .001) compared to the baseline model, but the linear slope could be held equal in the authoritarian and authoritative classes (0.212) on the one hand and the indulgent and uninvolved classes (0.317) on the other (χ2(87) = 197.61; RMSEA = .07; CFI = .95). Consequently, the final multigroup model provided an equally good fit (Δχ2(5) = 4.57, p = .47) as the baseline model. Initially, all children scored equally low on alcohol use and increased their alcohol use between Grades 6–12, with children of the indulgent and uninvolved classes demonstrating the steepest increases across time.
For cigarette use, a multigroup model with intercepts held equal in all classes (χ2(75) = 310.44; RMSEA = .11; CFI = .90) provided a worse fit to the data (Δχ2(3) = 8.88, p < .05) than the baseline model (χ2(72) = 301.56; RMSEA = .11; CFI = .91); when subsequently freeing the intercept for the authoritative class (0.016 as opposed to 0.073 for the other classes), the model (χ2(74) = 301.88; RMSEA = .11; CFI = .91) had an equally good fit (Δχ2(2) = 0.32, p = .85) as the less parsimonious baseline model. Next, a model in which the linear slope was held equal in all classes (0.017) except for the uninvolved class (0.093), and the quadratic slope held equal in the authoritarian and authoritative classes (0.026) on the one hand and the indulgent and uninvolved classes (0.046) on the other (χ2(78) = 303.14; RMSEA = .10; CFI = .91) provided a similar fit (Δχ2(6) = 1.58, p = .95) as the baseline model and, hence, was preferred on the basis of parsimony. Initially, all children scored low on cigarette use and children of the indulgent and especially the uninvolved class showed the steepest increases between Grades 6–12. Ancillary analyses demonstrated that boys and girls developed differently within the uninvolved class: the intercept could be fixed as equal (Δχ2(1) = 0.17, p = .68), whereas the linear (boys: 0.041, ns; girls: 0.310, p < .001) and quadratic slopes (boys: 0.055, p < .001; girls: 0.005, ns) could not (Δχ2(1) = 16.31, p < .001; and Δχ2(1) = 4.35, p < .05, respectively). Whereas girls of uninvolved parents increased linearly across time in smoking, boys of uninvolved parents tended to smoke less at Grades 7–10 but caught up with girls at Grade 11 and tended to smoke more at Grade 12.
For antisocial behavior, multigroup modeling indicated that none of the intercepts could be fixed as equal because any constraint on the intercept level was accompanied by a decrease in fit as compared to the baseline model. Hence, the intercept needed to be freely estimated in all classes as indicated in . Next, the linear slope could be held equal in the authoritarian and authoritative classes (0.041) on the one hand and the indulgent and uninvolved classes (0.097) on the other (χ2(251) = 610.36; RMSEA = .07; CFI = .90) which provided an equally good fit (Δχ2(2) = 0.48, p = .79) as the baseline model (χ2(249) = 610.088; RMSEA = .07; CFI = .90). Initially, children of the authoritative class scored lowest on antisocial behavior, followed by the authoritarian, indulgent, and uninvolved classes, respectively. Children in the indulgent and uninvolved classes demonstrated the steepest increases across time. Boys and girls developed differently in the uninvolved and authoritarian classes. In the uninvolved class, the intercept could be fixed as equal (Δχ2(1) = 3.03, p = .08), whereas the linear slope (boys: 0.157, p < .001; girls: 0.088, p < .001) could not (Δχ2(1) = 3.92, p < .05), indicating that both started off at the same level but boys increased much steeper. In the authoritarian class, the intercept (boys: 1.220, p < .001; girls: 0.591, p < .001) and linear slope (boys: 0.017, ns; girls: 0.063, p < .001) could not be fixed as equal (Δχ2(1) = 16.31, p < .001; and Δχ2(1) = 4.35, p < .05, respectively), indicating that boys started off at a higher level but girls increased somewhat more steeply across time.
For internalizing symptoms, a multigroup model with intercepts held equal in all classes (χ2(251) = 527.88; RMSEA = .07; CFI = .93) provided a worse fit to the data (Δχ2(3) = 10.89, p < .05) than the baseline model (χ2(248) = 516.99; RMSEA = .06; CFI = .93); when subsequently freeing the intercept for the univnvolved class (2.615 as opposed to 1.754 for the other three classes), the model (χ2(250) = 519.43; RMSEA = .06; CFI = .93) had an equally good fit (Δχ2(2) = 2.44, p = .30) as the less parsimonious baseline model. The linear slope could be held equal in all classes (0.191) but the quadratic slope could be held equal only in the indulgent and uninvolved classes (0.000) and needed to be freely estimated in the remaining two classes in terms of model fit. This final multigroup model (χ2(254) = 527.44; RMSEA = .06; CFI = .93) provided an equally good fit (Δχ2(6) = 10.45, p = .11) as the baseline model. Initially, children of the uninvolved class showed the highest levels of internalizing symptoms. All classes showed increases during the first few years but, for the authoritative class, these increases levelled off during childhood and were followed by decreases through adolescence.
In sum, the four longitudinal parenting classes obtained functioned as important moderators of child developmental trajectories through elementary and high school. Gender differences were only found with respect to cigarette use and antisocial behavior within the parenting classes.