Just a fraction of the nation’s children with disabilities and developmental delays may be accessing the early intervention services they need, a new advocacy group report suggests.

An analysis released Tuesday by Easter Seals indicates that fewer than 3 percent of kids are participating in the government-funded Individuals with Disabilities Education Act Part C program, which offers early intervention services to children up to age 3.

At the same time, estimates suggest that almost 13 percent of children across the country should qualify.

The report offers a state-by-state profile of the number of children served by the early intervention program. Six states stood out — Massachusetts, Rhode Island, New Mexico, Wyoming, New York and New Hampshire — for serving at least 4 percent of children.

Meanwhile, seven states and the District of Columbia provided early intervention to fewer than 2 percent of kids under age 3, the report found.

“With the right investment in treatment and therapy before the age of five, we can ensure every child in America can enter school ready to learn,” said Katy Neas, senior vice president of government relations at Easter Seals.

However, Neas and her colleagues note that the report offers just a piece of the picture. That’s because they say less than 20 percent of children in most states are properly screened for special needs.