You will need to design a health intervention that addresses a health problem or issue in a particular population. When we build interventions to improve health, we want to use theory that we know predict behavior change.
You will use the Transtheoretical Model (TTM) to change a particular behavior in a specific population. As such, you must select:
Population to study (children, adolescents, elderly, women, men, etc.)Health problem to change (teen pregnancy, smoking, etc.)
