If you're not familiar with one of my favorite authors, you may want to check out Seth Godin.

Godin says “A tribe is a group of people connected to one another, connected to a leader, and connected to an idea. A group needs only two things to be a tribe: a shared interest and a way to communicate.”

Most healthcare categories do not have tribes. Dermatology patients are not connected by an idea. They have no shared interest and thus no leader or way to communicate. Couples and individuals struggling with infertility are connected by an idea however. They are connected by the feeling of loneliness and exclusion. They are connected by the feeling that they want to know their problems are human.