- The overall incidence appears to peak @ 10 to 12 years. RAP is rare among children younger than 5 years of age, & an organic cause must be -considered even more carefully in this younger age group.

- Apley observed that males and females are affected equally in early childhood up until the age of 9.

- Between 9 and 12 years of age the female-to-male ratio approaches 1.5 to 1.

- Onset of chronic pain in a child younger than 4 years old requires a more in-depth organic evaluation, particularly for structural abnormalities.