Fig. 7
From: Trajectories of imitation skills in preschoolers with autism spectrum disorders
Imitation trajectories over time within the ASD group (n = 102). The trajectories at the group level (solid lines black = ASD1, nASD1 = 46, red = ASD2, nASD2 = 27, blue = ASD3, nASD3 = 29) are obtained using mixed-effect models [41, 42]. The 95% confidence interval of estimated group-level trajectory is represented in colored bands. Repeated time points of the same subjects are connected with dotted lines. The distribution in the subgroups was defined by the K-means clustering method in two steps. First clustering step yielded two clusters based on imitation skills raw scores at first time point. We retained the higher cluster (ASD1), and proceeded to the second clustering step performed on the slopes of imitation skills, yielding ASD2 and ASD3 subgroups