Four out of 10 adults who stutter have been denied a job or promotion and 82 percent of children who stutter have been bullied or teased, according to a new survey by the National Stuttering Association. People who stutter make up about 1 percent of the population.

Results of the survey were announced today at the organization's national conference in Scottsdale, AZ.

While there is no cure for stuttering, the survey of 1,235 people showed that speech therapy helps the majority of people who stutter. However, 30 percent of parents have received bad advice about stuttering treatment from pediatricians and speech therapists, and 14 percent of children who stutter have been denied speech therapy in school.

The survey also found that:

-- Stuttering interferes with work, school and family life. Children and adults who stutter often avoid speaking situations, feel embarrassed when people find out they stutter, and do not discuss their stuttering with family, friends and co-workers.

-- People who participate in stuttering support groups report fewer negative effects of stuttering and more successful speech therapy than those who do not. Support groups help people improve their self-confidence and develop positive attitudes about speaking and stuttering.

-- Speech therapies that change attitudes toward speaking and stuttering are more successful than therapies that focus on speech mechanics.

-- People who had speech therapy from a speech-language pathologist who is a Board Recognized Specialist in Fluency Disorders had more successful speech therapy than those who did not.

-- Alternative treatments for stuttering, such as psychological counseling, prescription medication and assistive devices, help some people but are significantly less effective than speech therapy.

Participants in the May 2009 online survey were National Stuttering Association members, participants in the organization's programs and visitors to its web site.