Adults with intellectual disabilities are struggling to find their place in the workforce, according to a new Gallup survey finding that two-thirds have no job.

Of those who are working, slightly more than half are employed in competitive environments alongside those without disabilities, while 38 percent work in sheltered workshops and 9 percent are self-employed.

The findings come from a national poll of more than 1,000 parents or guardians of adults with intellectual disabilities conducted for Special Olympics by Gallup and the Center for Social Development and Education at the University of Massachusetts Boston.

The results — published in the Journal of Vocational Rehabilitation — suggest that those with intellectual disabilities are participating in the labor force at about half the rate of typically developing adults.

“A meaningful job is important to most of us, and people with intellectual disabilities are no different,” said Gary Siperstein, director of the Center for Social Development and Education at the University of Massachusetts Boston and the lead researcher of the study. “Government has invested millions of dollars in better outcomes for adults with (intellectual disabilities) as they transition out of high school and into the labor force. Unfortunately, this study shows that we haven’t done enough.”

The survey found that among the roughly one-third who are employed, only 26 percent work full-time. And wages differed significantly depending on where individuals worked. Some 85 percent of those staffing sheltered workshops earned less than minimum wage while nearly all of those in competitive positions took home around or above the minimum in their state, researchers said.

Of the individuals with intellectual disabilities employed competitively, almost one-third worked in customer service, the survey found. Other popular fields included retail and food service while a smaller number of respondents cited office work, manufacturing or positions in landscaping, construction, childcare and animal care.

One positive finding, researchers said, is that the majority of those with intellectual disabilities who are employed — whether competitively or at sheltered workshops — have been at their current job for three years or more suggesting a high level of job security.