Q: How should I write the statement of the problem for a study on child abuse?
Your statement of a problem should explain clearly and precisely the details of what you want to study. This includes an issue statement, a proposed method to solve the problem at hand, and the vision. Your question mentions you wish to study a topic related to child abuse. As I am not aware of the aspects you are looking to study, it would not be possible for me to suggest a statement of the problem.
But you can refer to some excellent resources we have published that would help you to understand how to write the statement of a problem. Please go through them and try to come up with a problem statement for your research. For additional help, you can discuss your ideas with your colleagues or seniors.