Fig. 1

Trajectories of mental health difficulties for the 5-class model

Note: Year 7 (aged 11/12); Year 8 (aged 12/13); Year 9 (aged 13/14). Total difficulties: (1) low-stable (3,113/14,215; 21.9%), (2) medium-stable (5,305/14,215; 37.3%); (3) medium-increasing (1,366/14,215; 9.6%), (4) high-medium decreasing (3,105/14,215; 21.8%), (5) high-stable (1,325/14,215; 9.3%). Emotional difficulties: (1) low-stable (1,470/14,215; 10.3%), (2) medium-increasing (3,010/14,215; 21.2%), (3) medium-stable (5,762/14,215; 40.5%), (4) high-decreasing difficulties (2,118/14,215; 14.9%), (5) high-stable difficulties (1,855/14,215; 13.0%). Behavioural difficulties: (1) low-stable (2,066/14,215; 14.5%), (2) medium-stable (7,220/14,215; 50.8%), (3) high-medium-decreasing (3,538/14,215; 24.9%), (4) medium-increasing difficulties (532/14,215; 3.7%), (5) high-slightly-decreasing (860/14,215; 6.0%)