I wrote mine in this format: one page only
Intro about my background
Incident or specific event that made me choose that field
What I hoped to gain from my residency program (i.e for FP I wanted to be able to do it all, be alone in the wilderness, run an ER, be the hospitalist, run urgent care, do clinic medicine, etc) My vision for myself so I would be ready to practice on my own.
My vision for the next ten years, where I saw my career progressing
Conclusion