Fig. 4

Trajectory analysis plot of PrEP risk perception two categories in MSM population (we selected). The horizontal coordinate is the time of follow-up, and the vertical coordinate is the score of the PrEP risk perception. The red line represents “Category 1” (n = 493, 78.75%), with a low initial value of PrEP risk perception and a smoother overall level. We named “Category 1” as the “low-risk perception group”. The blue line represents “Category 2” (n = 133, 21.25%), with higher initial values of PrEP risk perception and a gradual decrease over time. We named “Category 2” as the “high-risk perception group”