Sunday 20 September 2015

Challenging Behaviour: ODD or PDA?

At our very first meeting with a paediatrician, the word 'oppositional' was used in reference to our younger daughter. 

Her diagnosis is written as:
1. Autistic Spectrum Disorder and 2. Oppositional behaviours/pathological demand avoidance behaviours.

Much as I loved our paediatrician for just 'getting it' (and by that I mean spotting the signs of autism straight away), and for giving us a quick diagnosis (not that I was pushing for one, it was all somewhat of a surprise to me), this diagnosis is what I would actually call sitting on the fence. Reasons for that are slightly complicated, but in a nutshell PDA is a relatively new diagnosis in medical terms and so not 'in the manuals' for diagnoses.

After a few months of searching for general information on autism, we experienced our 'lightbulb moment' when we stumbled across Pathological Demand Avoidance (PDA). We could tick almost all of the diagnostic criteria for our girl; the language delay with catch-up seemed particularly relevant. She was passive, resisted demands, led by a need to control, sociable and comfortable with role-play. The last two characteristics are not often associated with classic autism or Aspergers, and that is where we saw (and still see) the most difference.

We were lucky, I feel, to escape the suggestion of Oppositional Defiant Disorder as a diagnosis. It wouldn't have been right, but it would have been an obvious choice given that the word oppositional was being used.

Oppositional she may have been, but she definitely wasn't defiant. She also wasn't naughty. There may not have seemed to be a rhyme or reason for her refusal to do the most basic of tasks when younger, but we soon learned that there was. She didn't refuse to wear socks just because she wanted to be awkward, or just because we'd asked her to; it was a sensory issue. She didn't get irrationally distressed when we walked a different way to nursery just to annoy us; her fear of not being in control and not knowing what was happening was the cause of that.

In fact, we've come to learn that many of her refusals are sensory led. Others are anxiety driven; going to new places or the fear of being sick in the car prevent us from getting her out as much as we'd like. Of course many children have these worries, but they are not autistic, and the difference to us (having one older child who is also not autistic) was the extreme distress which it would, and does, cause our younger girl, and the long-lasting knock-on effects if we choose to force the issue.

So back to my original question: what is the difference between ODD (Oppositional Defiant Disorder) and PDA (Pathological Demand Avoidance)?

This diagram below, made by the PDA Society (, shows that PDA falls within the circle of Autistic Spectrum Disorders, whereas ODD does not. There are other common co-morbid conditions in the green circle which likewise do not require an Autistic Spectrum Disorder diagnosis to be valid.

A child (or adult) can be given an ODD diagnosis without an autism diagnosis; however every child/adult with PDA is autistic. There are various tests for Austistic Spectrum Disorder/Condition which can be found elsewhere online; the National Autistic Society is the best place to start looking for information on those.

Children with ODD are often described as having 'emotional and behavioural difficulties', or 'conduct problems'. They may have experienced difficult social environments and use behaviour as a means of attention, an outpouring for their anger or to hide their lack of self-worth. One difference often quoted between those with ODD or PDA is that children with ODD are less keen on embarrassing themselves in front of their peers; they are keen to fit in and can socialise in a typical way. Children with PDA on the other hand, are more likely to have unpredictable outbursts, even in front of their peers, and they tend to try and control all social interaction without understanding why their peers do not like it and then shun them.

It is possible to be autistic (whether that's Asperger Syndrome or Classic Autism) and have a co-morbid diagnosis of ODD. It is probably true to say that demand avoidance is there for most children with autism, especially when they are resistant to changes in routine. Children with PDA may enjoy some routine as it can lessen anxiety, but they are also keen to have control of their environment and so can be largely unpredictable. 'Jekyll and Hyde' personality is often mentioned in conjunction with PDA.

The diagram below shows the family of pervasive development disorders specifically, in a different way:

ODD is not mentioned above as this diagram is purely information on autistic spectrum disorders, which we have established ODD is not (ODD may be present in children/adults without ASD). There is crossover possible between most of these diagnoses however; you could for example, have a child diagnosed with Asperger Syndrome who shows PDA traits. It would be unlikely I feel (though certainly not impossible), to have a child diagnosed with PDA and ODD.

My worry is that some children are labelled ODD unnecessarily. There is a huge difference in the strategies which can be used successfully with either diagnosis and that's why I'd urge all parents to read up about all these conditions and what strategies there are. 
For PDA, I'd start with Strategies listed on the PDA Society page, or PDA behavioural strategies by Autism West Midlands. For ODD, take a look at Contact A Family's page. There is also a fantastic Facebook page called the Autism Discussion Page where many different strategies are suggested for varying situations and I thoroughly recommend it.

The term 'can't help won't' is often used to describe PDA. Traditional parenting methods, such as rewards and consequences, are not generally effective over a sustained period. They may work once or twice if all other conditions are favourable, but not when the need to avoid demands is strong. Maybe if you've tried the ODD strategies and they are not working, take a look at the PDA ones, or vice versa.

This is a topic which is likely to continue to draw much further discussion over the coming years as it is not a clear cut area. I think you need to remember that parents are experts, and no-one knows your own child as well as you. Go with your gut instinct and what works for your child and your family. The diagnosis DOES matter as it can back up your choice of strategies and a diagnosis will help educate others, but what is immediately more important is making sure that all those around your child are using helpful and consistent strategies.