Autistic females are flying under the radar of diagnosis because they're so good at camouflaging their behaviors, researchers have warned.

Around one in every 100 people are on the autism spectrum and there are around 700,000 autistic adults and children in the UK, according to the National Autistic Society.

And yet an autism diagnosis is made much more frequently, and at an earlier age, in males compared with females—at a rate of around four males to every female.

A new study by experts from the Center for Innovation in Mental Health at the University of Southampton, Liverpool Hope University, and University College London, has shed further light on just how adept females are at hiding—or what has been termed 'camouflaging' - their autistic traits in order to fit in, a behavior that could see them dodging a diagnosis and failing to get the help they need.

In a test of social reciprocal behavior—which includes a set of behaviors such as taking turns, following someone else's initiative, and being flexible—autistic females showed more advanced social presentation than males, despite both sexes having similar levels of autistic traits.

Dr. Henry Wood-Downie, who is now a Research Fellow at Southampton Education School, says that a better awareness of camouflaging could lead to increased support for those who might otherwise slip the net.

Commenting on the research, published in the Journal of Autism and Developmental Disorders, Dr. Wood-Downie suggested that: "We need to raise awareness of camouflaging in general, in terms of educating school staff, GPs and other practitioners, because there seems to be a lot of autistic females flying under the radar as things currently stand. And we want to raise this awareness so that girls who need it can access support at the earliest stage possible—because early intervention is usually key in promoting positive outcomes."

Some of the typical behaviors among children with autism include not responding to their name, avoiding eye contact, repeating certain phrases, struggling to understand what others are thinking and feeling, adopting strict routines, and also making repetitive movements, such as flapping hands, flicking fingers or rocking the body.

Autism is also associated with a number of strengths, including attention-to-detail, logical thinking, and having excellent memory for topics of interest.

On the whole, autistic girls may be quieter, hide their feelings, and may appear to cope better in social situations, meaning they may not display the stereotypical behaviors associated with autism.

And research suggests that these behaviors may reflect camouflaging—strategies used in social interaction to appear less autistic.

The study itself involved a group of 84 participants, aged between 8-14 year old, and included autistic and non-autistic male and female children and adolescents.

Crucially, some of the autistic participants scored highly on a measure of autistic traits, and where there had been concerns raised by schools and/or parents, but who didn't actually have a formal diagnosis of autism—the idea being that if you only include females with a formal diagnosis, you could be missing those who are camouflaging.

To measure behavioral camouflaging, participants took part in an Interactive Drawing Task, in which a researcher and young person took it in turns to create a drawing, such as a house, starting with just a simple line.

Dr. Wood-Downie says: "What you're trying to see is whether the child can work with you to make a joint drawing, to build on the gradual steps you both put in. You might, for example, change the drawing to see if the child or adolescent can be flexible with you, something that's thought to be hard for many children with autism."

Reciprocal behavior efforts were awarded points if, for example, the child or adolescent made a meaningful contribution to the drawing or pushed the paper back across the desk after their turn ended—before an overall score was then given.

When it came to the female participants, autistic and non-autistic children and adolescents had almost identical scores—with autistic females achieving an average score of 2.91 compared with 2.89 in the neurotypical group.

But non-autistic male children and adolescents achieved much higher social reciprocity scores than non-autisic males. The gap between the scores was larger—2.16 in the autism group compared with 3.22 in the neurotypical cohort.

The results of the study support the idea of behavioral camouflaging where autistic females are presenting as similar to non-autisitc females.

In contrast, autistic males presented as very different to non-autisic males, even though autisitc males and females had very similar levels of autisitc traits.

Importantly, the study also measured participants' theory of mind, i.e., their ability to recognize the mental state of others.

This was investigated through a child-friendly version of the famous Reading the Mind in the Eyes test, in which participants look at a series of images when only a person's eye region was visible.

Children and adolescents then had to match the emotion being conveyed to one of four words—such as angry or happy.

The results showed that male and female children and adolescents had similar theory of mind scores. Because social reciprocity was much more advanced in females compared with male participants, this provides further evidence of compensatory camouflaging in autistic females.

So why is it so important for professionals to pick up on camouflaging?

Dr. Wood-Downie explains: "In general, early intervention is a good thing, and later intervention is usually associated with poorer developmental outcomes. If there are female individuals who are struggling, it's best to recognize this earlier in order to put appropriate support in place for those who need it. And, in fact, there is research to suggest autistic females only get picked up once they hit crisis point—i.e., they only receive an autism diagnosis once they've been referred to other mental health services for things like depression, anxiety and eating disorders."

Other research studies have found that some autistic males camouflage, and so these individuals are also at risk for similar mental health difficulties.

Dr. Julie Hadwin, of Liverpool Hope University's School of Education Studies and a member of Hope's Center for Education and Policy Analysis (CEPA), who contributed to the research, argues that "Camouflaging itself is something that can lead to difficulties."

"It's a stressful, effortful thing to do. Girls describe camouflaging as constantly having to be something they're not. And, of course, that's a really difficult thing to maintain."

"Females can have an identity crisis, as they're trying not to be themselves while at the same time engaging in camouflaging strategies that take a lot of effort leaves little in the way of spare capacity to engage in other things, like doing school work."

All of this, Dr. Wood-Downie argues, may point to the fact we may need to move the goalposts according to gender when it comes to diagnosing autism.

But Dr. Wood-Downie is also quick to point out that society's approach to autism should never be a one-way street.

He explains: "The focus shouldn't just be on autistic people. If society as a whole was more accepting of the social differences that autistic individuals often display, maybe they'd feel less need to try and camouflage. That's something I'm really keen to advocate. There's also something called the 'double empathy problem.' In the past, people, including researchers, have often assumed it's autistic individuals' problem with understanding others. But, actually, it goes both ways. Non-autistic people have trouble understanding autistic people, while autistic people have trouble understanding neurotypical people. It's a double lack of understanding that leads to difficulties."