Many men, and some women have large shoulder widths.
As a large shouldered back sleeper, you're most likely to need a medium profile pillow (i.e. a pillow with medium loft) since you're likely to have a broader frame/chest, and still need to fill the gap between your neck and your mattress. Next up is your sleep comfort, then we're done!
Question 3 will take you to your Pillow Number and show you your most suitable pillows.
