Table 3. GMM parameter estimates for general sleep disturbance scale latent classa solution with 7 assessments, with dyad as a clustering variable.
| Parameter Estimatesb | Lower Sleep Disturbance (0) n = 224 (88.5%) | Higher Sleep Disturbance (1) n = 29 (11.5%) |
| Means | Mean (S.E.) | |
| Intercept | 38.416*** (1.777) | 58.636*** (4.946) |
| Linear slope | −1.002 (0.708) | 6.314** (2.464) |
| Quadratic slope | 0.115 (0.099) | −1.247*** (0.296) |
| Variances | ||
| Intercept | 212.766*** (31.235) | 66.583 (35.399) |
| Linear Slope | 1.051 (0.540) | 8.544** (3.313) |
*
p<.05, **p<.01, ***p<.001.
a
Trajectory group sizes are for classification of individuals based on their most likely latent class probabilities.
b
Growth mixture model estimates were obtained with robust maximum likelihood, with dyad as a clustering variable to account for dependency between patients and caregivers within the same dyad. Quadratic slope variances were fixed at zero to improve estimation.
Abbreviations: GMM = Growth mixture model; S.E. = standard error.