For my theme I chose 'breast cancer' because recently the mother of someone I know was diagnosed with very advanced breast cancer, which could have been detected earlier if she had gone for regular mammograms.
I chose to use only a woman's silhouette because even though it is abstract, its shape is distinctive and recognizable enough. Plus placing the heading near the breast seems to draw attention to the area.

The body copy beneathe the head is small because the poster is meant to be printed out in A3 size ie. it's meant to be read after the poster has caught the attention of the reader, who wants more information. The body copy reads "Early detection can increase your chances of beating breast cancer. Schedule your mammogram today."
Comments from tutorial
My classmates loved the poster (even the girls). It was simple and effective. Even my tutor had to admit the poster's message and layout were clear (but not before asking me why the silhouette had no arms or why the breast didn't look diseased).
Again, simplicity rules! Go Occam's Razor!
