Narrator: This is Science Today. If you don't have a regular doctor, you're more likely to be hospitalized unnecessarily. Dr. Andrew Bindman of the University of California, San Francisco found that people with chronic conditions such as asthma were more likely to be hospitalized, rather than treated and sent home, when they didn't have a regular primary care provider.

Bindman: Individuals from lower income communities were more likely to be admitted to the hospital with these conditions. African Americans as well -- as compared to whites -- were more likely to be admitted with these conditions.

Narrator: However, Bindman says that while poor and inner city neighborhoods do have fewer doctors, that's not the only factor.

Bindman: I think health insurance is another important part of it. There are many people who live in communities where there are plenty of doctors around, but because of the nature of the type of work that people do, or their income, they do not have health insurance and so they do not have real access to those providers even though they may not be physically very far from them.

Narrator: Bindman says unnecessary hospitalizations cost about a billion dollars a year in California alone. For Science Today, I'm Steve Tokar.