Autism: Could high U.S. rate be due to over-diagnosis?

Updated 1205 GMT (2005 HKT) October 24, 2015

The main character in Ann M. Martin's 2014 book, "Rain Reign," is Rose Howard, a fifth-grader with high-functioning autism who loves homonyms, rules and prime numbers. Here are some other books for children and teens featuring characters on the autism spectrum.

Photos: Photos: Autistic characters in fiction

Autistic characters in fiction – The main character in Ann M. Martin's 2014 book, "Rain Reign," is Rose Howard, a fifth-grader with high-functioning autism who loves homonyms, rules and prime numbers. Here are some other books for children and teens featuring characters on the autism spectrum.

Hide Caption

1 of 18

Martin has written about children with autism before. "Inside Out" is about 11-year-old Jonathan's life with his 4-year-old brother, James, who is severely autistic, and the sacrifices their family makes so he can attend a school for autistic children.

Photos: Photos: Autistic characters in fiction

Autistic characters in fiction – Martin has written about children with autism before. "Inside Out" is about 11-year-old Jonathan's life with his 4-year-old brother, James, who is severely autistic, and the sacrifices their family makes so he can attend a school for autistic children.

Hide Caption

2 of 18

Martin's Newbery Honor book, "A Corner of the Universe," tells the story of 12-year-old Hattie, who connects with her Uncle Adam after he returns from being institutionalized for a condition involving schizophrenia and autism.

Photos: Photos: Autistic characters in fiction

Autistic characters in fiction – Martin's Newbery Honor book, "A Corner of the Universe," tells the story of 12-year-old Hattie, who connects with her Uncle Adam after he returns from being institutionalized for a condition involving schizophrenia and autism.

Hide Caption

3 of 18

"The London Eye Mystery" tells the story of 12-year-old Ted, who has Asperger's syndrome. He must overcome his difficulty reading people and use his skills in tracking numbers, facts and weather patterns to help his older sister find their cousin, Salim, who goes missing after riding the London Eye. It received the 2010 Dolly Gray Children's Literature Award, which recognizes "books that appropriately portray individuals with developmental disabilities."

Photos: Photos: Autistic characters in fiction

Autistic characters in fiction – "The London Eye Mystery" tells the story of 12-year-old Ted, who has Asperger's syndrome. He must overcome his difficulty reading people and use his skills in tracking numbers, facts and weather patterns to help his older sister find their cousin, Salim, who goes missing after riding the London Eye. It received the 2010 Dolly Gray Children's Literature Award, which recognizes "books that appropriately portray individuals with developmental disabilities."

Hide Caption

4 of 18

"The Curious Incident of the Dog in the Night-Time" is narrated by autistic 15-year-old Christopher Boone, who is mathematically gifted and literal-minded, as he investigates the murder of his neighbor's poodle. The book received the 2004 Dolly Gray Award.

Photos: Photos: Autistic characters in fiction

Autistic characters in fiction – "The Curious Incident of the Dog in the Night-Time" is narrated by autistic 15-year-old Christopher Boone, who is mathematically gifted and literal-minded, as he investigates the murder of his neighbor's poodle. The book received the 2004 Dolly Gray Award.

Hide Caption

5 of 18

"Anything But Typical" is told from the perspective of 12-year-old Jason Blake, who has high-functioning autism. Jason is happy to make a new friend, Rebecca, on an online writing forum called Storyboard but begins to stress over the possibility of interacting with her in person.

Photos: Photos: Autistic characters in fiction

Autistic characters in fiction – "Anything But Typical" is told from the perspective of 12-year-old Jason Blake, who has high-functioning autism. Jason is happy to make a new friend, Rebecca, on an online writing forum called Storyboard but begins to stress over the possibility of interacting with her in person.

Hide Caption

6 of 18

"Al Capone Does My Shirts" is the first in the "Al Capone" historical series by Gennifer Choldenko. It's set in 1935, when 12-year-old Moose Flanagan gives up playing baseball to take care of his older autistic sister when she is rejected by a school in San Francisco, while their father works as an electrician at the prison on Alcatraz Island.

Photos: Photos: Autistic characters in fiction

Autistic characters in fiction – "Al Capone Does My Shirts" is the first in the "Al Capone" historical series by Gennifer Choldenko. It's set in 1935, when 12-year-old Moose Flanagan gives up playing baseball to take care of his older autistic sister when she is rejected by a school in San Francisco, while their father works as an electrician at the prison on Alcatraz Island.

Hide Caption

7 of 18

Cynthia Lord's Newbery Honor Book "Rules" follows 12-year-old Catherine and her relationship with her younger brother, David, who has autism. But teaching her brother about the rules of life causes her to question what "normal" really means.

Photos: Photos: Autistic characters in fiction

Autistic characters in fiction – Cynthia Lord's Newbery Honor Book "Rules" follows 12-year-old Catherine and her relationship with her younger brother, David, who has autism. But teaching her brother about the rules of life causes her to question what "normal" really means.

Hide Caption

8 of 18

Kathryn Erskine's National Book Award winner "Mockingbird" tells the story of fifth-grader Caitlin, who has Asperger's syndrome and lives in a black and white world. But her life is shattered when her caring brother is killed in a school shooting and she has to figure out the world without him.

Photos: Photos: Autistic characters in fiction

Autistic characters in fiction – Kathryn Erskine's National Book Award winner "Mockingbird" tells the story of fifth-grader Caitlin, who has Asperger's syndrome and lives in a black and white world. But her life is shattered when her caring brother is killed in a school shooting and she has to figure out the world without him.

Hide Caption

9 of 18

"Waiting for No One" chronicles 18-year-old Taylor's life with Asperger's syndrome, her struggle for independence and how she connects with Samuel Beckett's play "Waiting for Godot." The book is the recipient of the 2012 Dolly Gray Children's Literature Award.

Photos: Photos: Autistic characters in fiction

Autistic characters in fiction – "Waiting for No One" chronicles 18-year-old Taylor's life with Asperger's syndrome, her struggle for independence and how she connects with Samuel Beckett's play "Waiting for Godot." The book is the recipient of the 2012 Dolly Gray Children's Literature Award.

Hide Caption

10 of 18

In "Clay," 11-year-old Elsie and her autistic younger brother, Tommy, have been kidnapped by their emotionally unstable mother, and Elsie has to take risks to save them both.

Photos: Photos: Autistic characters in fiction

Autistic characters in fiction – In "Clay," 11-year-old Elsie and her autistic younger brother, Tommy, have been kidnapped by their emotionally unstable mother, and Elsie has to take risks to save them both.

Hide Caption

11 of 18

In "Delightfully Different," Mia is musically gifted and has an impressive vocabulary, but her school counselor makes her feel guilty for having Asperger's syndrome. Instead of cowering, Mia strives to prove her wrong. "Delightfully Different" received the Bronze Award by the Young Voices Foundation.

Photos: Photos: Autistic characters in fiction

Autistic characters in fiction – In "Delightfully Different," Mia is musically gifted and has an impressive vocabulary, but her school counselor makes her feel guilty for having Asperger's syndrome. Instead of cowering, Mia strives to prove her wrong. "Delightfully Different" received the Bronze Award by the Young Voices Foundation.

Hide Caption

12 of 18

In "Remember Dippy," Johnny's dread over spending the summer with his autistic older cousin, Remember, turns into the best summer of his life as they bond over shared experiences. The book received the 2014 Dolly Gray Children's Literature Award.

Photos: Photos: Autistic characters in fiction

Autistic characters in fiction – In "Remember Dippy," Johnny's dread over spending the summer with his autistic older cousin, Remember, turns into the best summer of his life as they bond over shared experiences. The book received the 2014 Dolly Gray Children's Literature Award.

Hide Caption

13 of 18

In "Screaming Quietly," Ian lives two lives. At school, he's on the high school varsity football team and dating a popular cheerleader. At home, his parents are divorced, and he has to look after his autistic brother, Davey. What happens when the two worlds collide?

Photos: Photos: Autistic characters in fiction

Autistic characters in fiction – In "Screaming Quietly," Ian lives two lives. At school, he's on the high school varsity football team and dating a popular cheerleader. At home, his parents are divorced, and he has to look after his autistic brother, Davey. What happens when the two worlds collide?

Hide Caption

14 of 18

The highly intelligent title character of "Colin Fischer" has Asperger's syndrome and uses index cards to recognize facial expressions. He becomes a modern-day Sherlock Holmes when he takes on the mystery of who left a gun in his school's cafeteria.

Photos: Photos: Autistic characters in fiction

Autistic characters in fiction – The highly intelligent title character of "Colin Fischer" has Asperger's syndrome and uses index cards to recognize facial expressions. He becomes a modern-day Sherlock Holmes when he takes on the mystery of who left a gun in his school's cafeteria.

Hide Caption

15 of 18

"The Half-Life of Planets" is told in alternating chapters from the perspectives of Lianna and Hank, whose initial encounter brings together an aspiring planetary scientist and a guitar enthusiast with Asperger's syndrome in a star-crossed way.

Photos: Photos: Autistic characters in fiction

Autistic characters in fiction – "The Half-Life of Planets" is told in alternating chapters from the perspectives of Lianna and Hank, whose initial encounter brings together an aspiring planetary scientist and a guitar enthusiast with Asperger's syndrome in a star-crossed way.

Hide Caption

16 of 18

In "Marcelo in the Real World," 17-year-old Marcelo Sandoval has Asperger's syndrome, hears music in his head and is obsessed with religion. But Marcelo's father pushes him to work in the mail room of a law firm, even though he has to deal with people trying to take advantage of him. The book is the winner of the 2010 Schneider Family Book Award, which honors authors or illustrators whose books embody "an artistic expression of the disability experience for child and adolescent audiences."

Photos: Photos: Autistic characters in fiction

Autistic characters in fiction – In "Marcelo in the Real World," 17-year-old Marcelo Sandoval has Asperger's syndrome, hears music in his head and is obsessed with religion. But Marcelo's father pushes him to work in the mail room of a law firm, even though he has to deal with people trying to take advantage of him. The book is the winner of the 2010 Schneider Family Book Award, which honors authors or illustrators whose books embody "an artistic expression of the disability experience for child and adolescent audiences."

Hide Caption

17 of 18

In "Eye Contact," autistic 9-year-old Adam is a silent witness and survivor of an attack that killed his playmate in the woods behind their elementary school. Only his mother can decode his behavior for clues about what really happened.

Photos: Photos: Autistic characters in fiction

Autistic characters in fiction – In "Eye Contact," autistic 9-year-old Adam is a silent witness and survivor of an attack that killed his playmate in the woods behind their elementary school. Only his mother can decode his behavior for clues about what really happened.

Hide Caption

18 of 18

(CNN)A report from the Center for Health Statistics finds that 13% of children who were diagnosed with autism spectrum disorders lose their diagnosis after later tests. The study, which uses data from the Centers for Disease Control and Prevention, is the first to look at a large, nationally representative sample of children.

One in 68 children in the United States are believed to have an autism spectrum disorder, a 30% increase from earlier estimates; in 2012 it was believed 1 in 88 children were on the spectrum, the CDC says. The diagnosis reversals are important to note for scientists who have puzzled over why there is such a big increase in the number of cases.

Researchers say some children who are given the autism label may in fact be struggling with other challenges, such as developmental delays or attention issues. Of the parents who were surveyed about the reversed diagnoses, about 74% thought the reversals were due to new information, meaning their child started to show developmentally appropriate social skills or language abilities, as opposed to a child being "cured." However, there have been some small studies that show early intervention with a child has shown promise.

The authors say some reversals may be due to the way children are screened. Pediatricians are encouraged to use developmental screening tests with all children regardless of any signs a child has a problem. Having a nonspecialist diagnose a child may be adding to the increase in numbers; so may an increased awareness about autism spectrum disorder, the authors say.

Scott Badesch, president and CEO of the Autism Society, agrees. "Better diagnosis occurring, as well as greater awareness of signs of autism being known, is also leading to more people being diagnosed as well," Badesch said. He also agrees with the authors that "additional research is needed before any one or more causes can be positively defined as the reason for the increase."

More research will be needed to determine if over-diagnosis has become more common, but the work does show that a child's diagnosis can sometimes change as the children get older and doctors learn more about the child.