WHAT THE LITERATURE AND RICHARD WOODS SAY ABOUT NEWSON ET AL (2003).
These are my notes on Newson et al (2003), the first peer reviewed PDA article. I have produced them as I am delivering a seminar on PDA soon, and I asked the students to critically review the article. I initially planned to include all the critique in the seminar, but I soon realised this was not possible due to the sheer amount of it. This is part literature review of the comments on Newson et al (2003), and large parts my own thoughts on the article. There are two sections, the first are general comments about the article and research. The second is my deconstruction of the Surface Sociability trait as described Newson et al (2003). The comments are not provided in any particular order or structure. I hope you find the notes useful.
I have some edits to typos, to improve readability and to provide some more information where relevant.
General observations and critique of Newson et al (2003) :
- Research is sourced from a single clinic in Nottingham, UK. Sample is not representative of general population. Research has a selection bias, as research sample is derived from referrals to a dedicated “Coding Disorders” clinic. Coding issues is when a person does not process/ make sense of certain aspects of communication.
- PDA was diagnosed as a standalone construct, not as “ASD + PDA traits”, one cannot be sure all persons with PDA are autistic. This seems linked to why Newson never systematically researched autism features (O’Nions et al, 2015).
- Newson did not systematically investigate features of autism (O’Nions et al, 2015). This is to be expected as Newson originally proposed PDA to be a new type of disorder, a “Pervasive Developmental Coding Disorder”. See relevant diagram. Newson spent 15 years(1988 – 2003) researching this behaviour profile. Profile is “surprisingly robust” and fundamentally unchanged. “Clearly, “hanging together as an entity” is not enough if that entity is not significantly different from both autism and Asperger’s syndrome, either separately or apart.” (Newson et al, 2003, p599). PDA is still a Pervasive Developmental Coding Disorder…
- Newson did not collect data on intelligence of their participants, (O’Nions et al, 2015). “IQ in these children tends to be meaningless because of the severe demand avoidance, and alternative descriptive gauges of ability are used clinically.” (Newson et al, 2003, p595). To me this seems a valid rationale, if one accepts that persons with PDA naturally present obsessive demand avoidance.
- If one is to assess intelligence in autistic persons, the best tool to use Raven’s Progressive Matrices (Soulières et al, 2011).
- Did not use any validated tools, used a semi-structured interview of their own creation (Newson et al, 2003; O’Nions et al, 2014).
- Did not establish the validity or specificity of PDA (Garralda, 2003; Green et al, 2018; Wing, 2002).
- “A few children whose clinical picture is less certain, often because of additional autistic characteristics, but atypical of autism also, were excluded.” (Newson et al, 2003, p596). Newson removed cases from her database if they presented autistic features, even atypical ones.
- Newson et al (2003) in their supplementary files explicitly argue that PDA is not an autism spectrum disorder and against conflating autism spectrum with Pervasive Developmental Disorders:
“It is useful to describe Asperger syndrome and classic autism together as forming the autistic spectrum; but in our view it is not useful to use ‘autistic spectrum disorders’ as synonymous with ‘pervasive developmental disorders’, as has become more prevalent lately in the UK. ‘Pervasive developmental disorders’ is the entirely satisfactory term of DSM-IV, in which each word has a relevant meaning to describe the nature of this ‘family’; it is acceptable to parent groups in the United States and Canada, and it is easily understandable when explained to parents in the UK, where lately it has been increasingly used by such groups. PDA is a pervasive developmental disorder but not an autistic spectrum disorder: to describe it as such would be like describing every person in a family by the name of one of its members.”
Newson et al, probably did this as their interpretation of Pervasive Developmental Disorders is different and wider than the accepted version of Pervasive Developmental Disorders. As Newson et al (2003) include non-autistic persons in their version, due to PDA and Specific Language Impairment. After all, why would anyone call non-autism conditions, autism now?
- PDA is not recognised by the main diagnostic manuals, the International Classification of Diseases (ICD) / Diagnostic and Statistical Manual of Mental Disorders (DSM) (Woods, 2018).
- PDA overlaps: Oppositional defiant disorder (ODD), Attention deficit hyperactivity disorder (ADHD), social anxiety disorder and may have been precursors of a schizotypal disorder. There is evidence to support ADHD element. Flackhill et al (2017) indicates PDA can found in persons with ADHD. Egan et al (2020), found that PDA can be predicted by ADHD. Personality precursors are seen in persons with PDA (Egan et al, 2019; Egan et al, 2020). High
- Strengths and Difficulties Questionnaire (SDQ) conduct and hyperactivity scores plus a clinical diagnosis of anxiety were highly predictive of scores above the pathological demand avoidance threshold on the Extreme Demand Avoidance Questionnaire (EDA-Q) (Green et al, 2018).
- “Some of the features outlined (for example sense of identity, price and shame) would be especially difficult to identify reliably” (Garralda, 2003). For instance, “Five of these respondents are afraid of their child, and 16 are afraid for her.” (Newson et al, 2003, p596).
- PDA might be a form of either attachment disorder or personality disorder (Christie, 2007).
- “Elizabeth Newson described a behaviour pattern she called “Pathological Demand Avoidance Syndrome” (PDA). Among other features, the children concerned use many strategies to avoid responding to demands. They also seem to find reward in upsetting other people. Children with any type of autistic disorder can show these behaviours so the idea that PDA is a separate syndrome remains unproven.” (Wing, 2002, p30).
- Aetiology is wrong. Newson et al proposed that PDA and autism are 100% caused by genetic or biological factors. Mental health disorders are social constructs and lack evidence of biomarkers for diagnostic purposes (Rutter and Pickles, 2016). A former Pervasive Developmental Disorder (PDD), Rett’s Syndrome was removed from DSM5 for being associated with a specific gene (Thomas, 2017). This is an example of how Newson made some large assumptions about PDA.
- PDA needs an equivalent evidence base to ASD, in the DSM5. “The nature of the analysis undertaken was not specified, but because the process was circular (i.e., starting with a predefined syndrome and then showing that it is different from other syndromes), this method would not be considered robust or convincing nowadays without replication within a large independent dataset, with additional demonstrations of discriminant and predictive validity.” (Green et al, 2018, p458).
- Newson’s sample is not representative of wider autism gender ratios, it has too many females in. This has biased Newson’s behaviour profile to include “Comfortable in role play and pretending.”, as this feature is seen more often in autistic females, than males. This trait did not significantly correlate with other diagnostic traits in Ellie Bishop’s research with the EDA-Q (2018). Assumes PDA is an autism subgroup though and Newson’s persons with PDA are autistic, which are both poor assumptions to make.
- The balanced gender ratio of Newson et al (2003). However, other clinical studies have gender ratios containing more males than females, specifically 1.25:1 of Gillberg et al (2015) and 2:1 of O’Nions et al (2016a). Eaton (2018) does have 1:1 gender ratio, but that research appears to have a number of substantial limitations.
- To highlight the problems with Newson’s research to establish PDA as a Pervasive Developmental Disorder. It is akin to comparing Reactive Attachment Disorder (RAD) & Disinhibited Social Engagement Disorder (DSED) to PDA. RAD & DSED are 2 types of attachment disorder, but simply comparing PDA to DSED & RAD does not make PDA an attachment disorder; all that has been done is showing PDA is different to DSED & RAD. Similarly, saying PDA belongs to the Attachment Disorders diagnostic grouping does not make PDA an attachment disorder. For PDA to be an attachment disorder it would need to conform to accepted understandings of attachment disorders.
- “Lightbulb moment”, making sense to caregiver’s, other stakeholders. I would argue this is to be expected considering PDA seems to be an “inverse-autism” from being the opposite of many autism stereotypes, see Table 1. Especially when accounting for extreme behaviours present, it should resonate strongly in persons, who are often vulnerable themselves from their own high anxiety levels (Dura Villa, 2018). The behaviours described by Newson, are often extreme and would be difficult for many persons to deal with over a sustained period of time. One can empathise with PDA caregivers, that they will often be desperate for appropriate support and understanding of their child. When one considers this, is it surprising that many caregivers’ have the “Lightbulb Moment” upon discovering PDA?
- Newson viewed PDA as being less functional than Asperger’s Syndrome, see article supplementary notes.
- Have 150 vs 111 of Help4Psychology database (Eaton, 2018).
- Trying to help lay persons, mainly caregivers (Newson, 1989; 1996; Newson et al, 2003). For example, Newson created her own “Pervasive Developmental Coding Disorders” diagnostic grouping as she thought autism spectrum was too narrowly defined, allowed dyslexia to be included and it is wholly understandable to lay persons, such as caregivers (Newson, 1996).
- PDA has different educational approaches to autism, does it? Many autism approaches do not work for most autistic persons (Milton, 2013). Behavioural based approaches do not work for PDA (Newson et al, 2003). What evidence does Newson actually have for many of their claims?
- I would argue all Newson really did was show that PDA is substantially different to autism, which is what she was trying to do, not make a new autism subgroup. I.e. O’Nions et al (2016) are incorrect there to try to make PDA a meaningful autism subgroup. This is makes sense, if one considers the autism subtyping literature; ALL attempts to divide autism have failed, by both biomarker and behavioural methods (Woods, 2019b; 2020b); i.e. autism cannot be successfully divided. So the fact that Newson’s results show PDA is not different does indicate that PDA is not autism. I suspect it is this reason why O’Nions et al (2016) when trying to make PDA a meaningful autism subgroup, attempt to do this using features that are not typical of autism. If a feature is not typical of autism, it is unlikely to be used to diagnose autism and instead be associated to a co-occurring condition. Such as “Fantasising, lying, cheating, stealing” and “Inappropriate sociability (rapid, inexplicable changes from loving to aggression)” (O’Nions et al, 2016, p415). This means that O’Nions et al (2016) are using features that do not represent to identify autism. I.e. PDA cannot be autism if it is composed by features that are not associated to autism. I would ask, do we actually want such “PDA” features being associated with autism?
- There are clinical differences between PDA and autism, including:
(1)PDA strategies that involve novelty, spontaneity and humour contradict the traditional autism approaches that rely on structure;
(2) The fantasy/ roleplay PDA trait is often absent or delayed in autistic persons;
(3) The frequency and variety of manipulative behaviours expressed by persons with PDA are not seen in autistic persons (O’Nions et al, 2015);
(4) Surface sociability issues in PDA are attributed to deficits in social identity, not to deficits in Theory of Mind, as is thought to be the case for autism (Newson et al, 2003);
(5) Newson viewed some of PDA behaviours to be linked to panic or fear. The PDA literature recognises anxiety is a co-occurring difficulty for autism (Gould and Ashton-Smith, 2011).
(6) PDA has a more balanced gender ratio than autism has (Newson et al, 2003).
- PDA behaviours might not be caused by autism, including having “psychopathic tendencies” and therefore is a double-hit (Wing et al, 2011).
- “The publications on PDA have attracted great interest and some controversy. The overriding reason for the interest has been in the strong sense of recognition expressed by both parents and professionals of the behavioural profile so cogently described and just how different it is from conventional understandings of ASD. The controversy, particularly among the medical community, has been about whether PDA does exist as a separate syndrome within the pervasive developmental disorders or whether it is part of the autism spectrum. For example, Wing and Gould (2002) feel that PDA is not a separate syndrome and that the individual behavioural features portrayed in the constellation described as PDA can be found within individuals with an autistic spectrum disorder. They agree, however, that ‘recognition of this subgroup with special problems is innovative and clinically valuable.” (Christie, 2007, p5). Wing and Gould did develop 15 unpublished PDA DISCO questions in 2002 (O’Nions et al, 2014), see Gillberg et al (2015). Note the sentence about how different PDA is from conventional (stereotypical) autism understandings, this supports my point about PDA is based against autism stereotypes. The point made by Wing and Gould, about how PDA features are found in autism, also show how there is nothing unique to autism. Furthermore, that people should not define a person by any mental health disorder diagnostic criteria as they are abstract representations of cognitive processes we often view as a syndrome (a clustering of symptoms). A logical extension is, if PDA is seen in autistic persons, it should also present in non-autistic persons. There is an argument that Christie, Gould and Wing worked in highly specialised autism settings (Sutherland House School and the Lorna Wing Centre, respectively in 2007). Do they have clinical experience and knowledge to have representative views of how PDA might present in general population? Is there clinical opinion really enough to say PDA is an autism subgroup?
- “Despite increasing acceptance that the PDA profile Newson described does exist in some children on the autism spectrum, the data that led to the proposal of PDA as a sub-group may have been influenced by the type of referrals that Newson’s specialist centre received, leading to a “collider bias”. Given the high threshold of severity required for assessment at the time, Newson likely assessed the most severe cases, both of ‘prototypical’ autism, and of PDA. This pattern means that milder presentations of ASD and PDA were unlikely to be present in her sample. Therefore, her data may over-estimate the degree to which PDA separates as a sub-group within the autism spectrum as we now know it.” (O’Nions and Eaton, 2020).
This is not an accurate representation of Newson’s work. Newson did not propose PDA as an autism subtype; she was explicit in that PDA is not an autism spectrum disorder. There are indicators that Newson went out of her way to ensure PDA is clinically different to autism, such as not basing PDA on the triad of impairment, or excluding atypical cases of PDA with autism features. Newson’s interpretation of Pervasive Developmental Disorder is also clinically broader than accepted version. I discuss these points throughout this blog.
The exact critique Newson’s research might have a collider bias due to individuals requiring a high threshold for clinical assessment. There is data we can use to investigate if this is a valid criticism. We have the following data
1975 – 0 cases.
1980 – 12 cases.
1988 – 36 cases.
1996 – 120 cases.
2000 – 150 cases (Newson, 1996; Newson et al, 2003).
We can calculate rates of diagnoses per year using these stats, the two figures that matter are 3 per year between 1975 to 1988, and 9.5 per year between 1989 -2000. This is during the 1980s, mainly due to the efforts of Lorna Wing and others the autism was being fundamentally broadened with the inclusion of Asperger’s Syndrome, to create an autism spectrum based on the triad of impairment of Wing and Gould (Frith, 1991). Wing first proposed Asperger’s Syndrome in 1981. First diagnostic criteria were in 1989 and revised by Christopher Gillberg in 1991. The first international conference on Asperger’s Syndrome was in 1988. Uta Frith translated Hans Asperger’s seminal work in 1991. Asperger’s was formally included in the two main diagnostic manuals in 1992 and 1994 (Attwood, 2015). Returning to the figures of 3 cases per year up to 1988, afterwards 9.5 per year; the rate more than tripled after 1988, and this happens coincided with broadening of the autism spectrum due to the acceptance of Asperger’s Syndrome. If there is a “collider bias” present in the sample, it would be present in about around a quarter of Newson’s sample.
- Ellie Bishop acknowledges Newson et al (2003) view that PDA is surface sociability is due to problems coding identity and social hierarchy. However, goes onto argue it can be better explained by deficits in Theory of Mind, due to assuming PDA is an autism subgroup. Bishop also acknowledges Newson diagnosed PDA as a standalone construct. Bishop does ignore how her results that PDA traits are not associated to Theory of Mind supports Newson’s views. The EDA-Q is based on Newson’s behaviour profile (O’Nions et al, 2014), so the EDA-Q does not measure “Coding issues” relating to Theory of Mind deficits. This is a reason why Bishop should have predicted that PDA is not associated to Theory of Mind.
- There are no features specific to autism (Beardon, 2017; McGuire, 2016). There are no features specific to PDA (Christie, 2007; Christie et al, 2012; Garralda, 2003; Malik and Baird, 2018 Milton, 2013; Wing, 2002). It is possible to be clinically diagnosed with autism and not be autistic, see “Quasi-autism”. Also attachment disorder can look like autism, “Attachment-based autism” from when attachment process is interrupted. (Woods, 2019c). For commentary on specificity of individual PDA traits, see table 2 from Orm et al (2018). I do not agree with all their comments.
- Signs Newson saw an extreme anxiety/ distress response. Disassociating, is represented in the comfortable in roleplay and pretend, sometimes confusing fantasy with reality. Lacking a sense of identity/ pride/ shame is seen in persons who experience trauma, anecdotal evidence in autistic persons (Milton, 2017). How some behaviour are due to panic, indicates fear. Other indicators, include overlap with attachment disorder.
- Newson et al research is from a single clinic. Autism history and literature would indicate that we should be wary of drawing too many conclusions from such research. Kanner and Asperger both discovered autism and drew very different conclusions about its nature. Kanner outlook was that autism was a rare childhood condition that held back autism understanding for decades, compared to the autism spectrum concept encouraged by adopting Asperger’s Syndrome perspectives. Kanner’s autism was more severe, less functional than Asperger’s Syndrome. Newson viewed PDA to be less functional than Asperger’s Syndrome (2003, see support material). Autism presents differently in different populations, many argue that we need different diagnostic thresholds for those not conforming to male biased DSM-5 criteria (See Eaton, 2017). Many persons who do not conform to autism stereotypes often struggle to get an autism diagnosis under DSM-5 (Evers et al, 2020). If a clinic sees the “same person” over and over again, it is possible it forms its own culture of practice, with ideas and stereotypes as to what autism or PDA might look like. An influential study from 12 clinics in the United States of America found that the best predictor of a Pervasive Developmental Disorder (accepted definition, not Newson’s grouping), found the best predictor of a specific diagnosis a person received was the particular clinic they attended (Woods, 2020b). Demonstrating that such communities of practice exist for autism. There are examples of community of practice present in PDA research samples, with a wide range of clinical thresholds. For example, Help4Psychology do not strictly follow the DSM-5, they have different criteria for autistic females:
“Professionals and teams working with children need to become aware of the ways in which girls can mask their difficulties, and need to move away from using the DSM as a ‘bible’. Stating that someone does not fulfil criteria, when these criteria are based on upon a ‘male’ presentation of a disorder, is short sighted in the extreme.” (Eaton, 2017, page 176).
This raises questions about representative is their PDA research of broader autism clinical practice?
Additional Help4Pscyhology use their own PDA definitions for “Extreme Demand Avoidance”:
“Demand avoidance had been present since early infancy and presented across contexts and time.”
“Avoidance is pervasive and often seems illogical or perverse (e.g. the child may be unable to eat whilst hungry)”
“Avoidance is not limited to a specific activity (or activities, e.g. school) or activities in a specific context.” (Eaton, 2019)
I do not know the logic or rationale for behind these definitions. Eaton (2019) states based on their examination of current literature & “extensive clinical knowledge” was used to create an informal algorithm. They do contradict other PDA experts views on people can transition into PDA (Newson, 1989; Newson et al, 2003), and other proposed autism subtypes (Wing et al, 2011). At the other end Gillberg et al (2015), have low thresholds for a PDA diagnosis:
“Individuals with a Total PDA score of 5 or were—based on clinical experience, not on systematic evidence—considered High-scorers, suggesting that in clinical practice they would have been given a diagnosis of PDA. “Classic PDA” was defined as Total PDA score of 5 or more and including the presence of socially manipulative or shocking behaviour to avoid demands.” (p981).
This threshold is lower than Newson et al (2003), as they observed social manipulative demand avoidance to be universal; it was not an “either/ or” trait with “shocking behaviour”. Worth noting that many predicted PDA populations and prevalence rates are based on such lower diagnostic thresholds (Gillberg et al, 2015). There appears to be a continuum of clinical outlook and diagnostic thresholds to PDA between the extremes of Help4Psychology and Gillberg et al (2015). For instance, the EDA-Q screening tool has been used as the primary instrument as part of diagnosing PDA (Lyle & Leatherland, 2015; Reilly et al, 2015). This raises the question how representative of broader PDA diagnoses is the Help4Psychology PDA definitions?
An indicator to this answer can be found in Help4Psychology “Rational Demand Avoidance” (not called PDA) group, which contains autistic CYP presenting PDA behaviour around 5 – 7 years old. Often triggered from aversive school experiences (Eaton, 2018). Worth mentioning that multi-agency pathway for PDA is partly intended to prevent an autistic child’s presentation deteriorating (Summerhill and Collett, 2018).
Research is supporting some divergent opinions on PDA (Woods, 2020c). It is possible that future research will present PDA differently to Newson’s profile, especially when looking in non-autistic populations.
- Comparison to Help4Psychology PDA database. Has 150 persons gathered over at least 25 years and 2 subsequent clinics in Nottingham. Help4Psychology 111 persons with PDA over 2 years from one clinic in Norwich. Newson seems to have broader definitions of PDA than Help4Psychology. Newson accepted persons can transition into PDA and not all behaviour profile traits are required for a diagnosis. Newson was trying to show PDA is different to “Kanner’s autism” and Asperger’s Syndrome, originally did not view PDA to a “Pervasive Developmental Disorder”; i.e. part of the autism spectrum. Help4Psychology view PDA as an autism subtype (Woods, 2020b).
- Newson views Autism spectrum to be comprised of “Classic Autism” and Asperger’s Syndrome, that the difference between the 2 is the person’s intelligence impacting how symptoms are expressed. She views PDDs to be broader than the autism spectrum, so that PDDs include non-autism conditions like Specific Language Impairment and so the diagnostic grouping included non-autistic persons. Pervasive Developmental Disorder – Not Otherwise Specified (PDD-NOS) were defined as someone not meeting threshold for ASD/ PDA/ Specific Language Impairment:
“Occasionally a child will show a cluster of symptoms that falls between these typical clusters. This is described as non-specific pervasive developmental disorder.” (Newson et al, 2003, p598).
Referring to the above cluster and her Figure 1 The “family” of pervasive developmental disorders. This is broader than the accepted definition of Pervasive Developmental Disorder and PDD-NOS. The accepted Pervasive Developmental Disorders diagnostic grouping contains, Asperger’s Disorder, Autistic Disorder, Childhood Disintegrative Disorder, Pervasive Developmental Disorder Not Otherwise Specified (PDD-NOS), and Rett’s Syndrome. The accepted version of PDD-NOS is that it is a residual category for those not meeting clinical threshold for autistic disorder (classic autism) and Asperger’s Syndrome, i.e. someone who had some, but not all of the features of autistic disorder/ Asperger’s Syndrome. There specific definition from the DSM-4 is only a single paragraph:
“This category should be used when there is severe and pervasive impairment in the development of reciprocal social interaction associated with impairment in either verbal or nonverbal communication skills or with the presence of stereotyped behavior, interests, and activities, but the criteria are not met for a specific Pervasive Developmental Disorder, Schizophrenia, Schizotypal Personality Disorder, or Avoidant Personality Disorder. For example, this category includes “atypical autism” – presentations that do not meet the criteria for Autistic Disorder because of late age at onset, atypical symptomatology, or subthreshold symptomatology, or all of these.” (Autism Speaks, 2020).
This means later approach to PDA as an autism subgroup, (for example, please see O’Nions et al, 2016) is narrower than Newson’s approach to PDA.
- Assumed anyone who had a Pervasive Developmental Disorder (her definition) has “Coding” (failure to process or make sense of certain aspects of communication) Issues. Is this accurate or helpful? Social Communication issues are common in mental health disorders (Wilkinson, 2016).
- Not all features and traits were required for a PDA diagnosis. For instance “Socially Manipulative Demand Avoidance” was displayed by 5.5 years, one case by 6.9 years. At least 10 different types of demand avoidance. The point here is that not all developmental traits (features) had to be displayed for a person to receive a PDA diagnosis. This also overlaps the 5 – 7 age range of onset for “Rational Demand Avoidance” group. This “Rational Demand Avoidance group displayed PDA behaviours, often after experiencing aversive school experiences (Eaton, 2018).
- As PDA is not similar to autism, in this case PDA is not based on the triad/ dyad of impairment and is clinically fundamentally different in its actually Restricted, repetitive patterns of behaviour, interests, or activities (RRBIs); it is a false-equivalence fallacy to include PDA in the autism spectrum.
- “The diagram shows clusters of symptoms (syndromes) which make up specific disorders within the “family”. (Newson et al, 2003, p598), this Newson describing her “The “family” of pervasive developmental disorders.” Diagram. She is literally telling us that PDA is not autism, by drawing it separate and not overlapping the autism spectrum. Again this makes sense when considers the feature s in Table 1.
- Personality and intelligence impact how symptoms and therefore syndromes are expressed in a person. Newson states elsewhere that high intelligence in autism is what marks Asperger’s out from Classic Autism (Newson, 1996; Newson et al, 2003).
- This is my observation, but if feels like Newson is trying to give PDA qualities of a natural kind. Something with fixed and know values that do change from human interaction with the kind (For discussion of what human and natural kinds are, see Woods, 2017). Newson argues that Pervasive Developmental Disorders all have coding issues, are related and are entirely genetic/ biologically caused (Newson et al, 2003). Like how PDA has different “Coding Issues” to autism, while ignoring how 20% of autistic persons pass theory of mind tests. Or how, because parents might fear their child, it does not reliably measure deficits in social identity/ pride/ shame. Newson is making some big assumptions about PDA and Pervasive Developmental Disorders, more broadly, while lacking the evidence to do so. Some of her opinions are later known to be false.
- Certain diagnostic traits are not used to identify PDA. The developmental traits: Passive early history, delayed speech development and neurological involvement. Were removed as some felt associated features were too common in the autistic population to accurately represent PDA, or to make a “meaningful subgroup” (O’Nions et al, 2016).
- Neurological Involvement trait has never been systematically researched in relation to PDA (Newson et al, 2003; Reilly et al, 2014). It is premature to remove a trait when we lack evidence about how it relates to PDA, or not.
- PDA is a misdiagnosis of autism for autistic females (Hughes, 2015). PDA is a female form of autism (Christie, 2007; Gould and Ashton-Smith, 2011).
- Allison Moore (Moore), contests that PDA is pathologising persons for displaying their self-agency, because a person challenges cultural norms and expectations. Moore argues it is powerfully in relation to children. She goes on to argue that autistic females are more likely attract a PDA identification. Moore correctly points out that PDA cannot be officially diagnosed as it lacks an agreed behaviour profile and standardised tools.
- The crucial points here is that most persons likely to not receive a Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM-5) autism diagnosis versus Diagnostic and Statistical Manual of Mental Disorders, 4th Edition (DSM-4) are those who do not meet autism stereotypes (Evers et al, 2020). Those who would be diagnosis of Asperger’s or Pervasive Developmental Disorder – Not Otherwise Specified PDD-NOS under DSM-4 do not conform to autism stereotypes; thusly unlikely to receive a DSM-5 autism diagnosis. Earlier, I present reasons how PDA does not conform to autism understandings, see (Woods, 2019a; 2020a; 2020c). I present the majority of these reasons below in Table 1, which sets out how PDA’s clinical descriptions compare to autism stereotypes. So it is clear that PDA does not conform to autism understandings and thus does not conform to autism stereotypes. Persons who would typically receive a PDA diagnosis would either receive a diagnosis of PDD-NOS or atypical autism. (Newson et al, 2003) That PDA might simply be relabelling of High Functioning Autism or Asperger’s Syndrome (O’Nions et al, 2015). People who would traditionally receive a PDA diagnosis, are unlikely to receive an autism diagnosis under the DSM-5, i.e. persons with PDA typically would not receive an autism diagnosis.
Table1: Autism stereotypes and corresponding points from PDA clinical literature.
|Autism Stereotypes.||PDA Clinical Literature.|
|Absent or delayed roleplay and pretend.||Comfortable in roleplay and fantasy.*|
|Are not sociable.||Are sociable, but it is surface.|
|Delays in social communication and interaction from Theory of mind deficits.||Surface sociability, appears to lack of sense of social identity, pride, or shame.*|
|Dislikes surprises.||Likes novelty.|
|Does not express strong emotions.||Intense emotions and dysregulation.|
|Does not make eye contact.||Makes eye contact.|
|Lacks empathy.||Manipulative demand avoidance behaviours.*|
|Likes routines and structure.||Dislikes routines and structure.*|
|Likes routines and structure being imposed upon them.||Has a need for control.|
|Passionate interest with unusual intensity/ focus.||Intense interests are often focused on people.|
|Should use clear and concise language.||Should use complex language to disguise demands.|
|There are many more autistic males, than females.||Female form of autism. Can be equally prevalent in both genders.*|
|Typical autism strategies (often behaviourism based, like Applied Behaviour Analysis) work.||Typical autism strategies (often behaviourism based, like Applied Behaviour Analysis) do not work.*|
*Are reasons why it is problematic conceptualising PDA as an autism subgroup.
Table 2: Criteria for Pathological Demand Avoidance Syndrome and clinical overlaps. From Orm et al (2018).
|PDA features (by Newson et al., 2003)||Overlaps / Do not overlap (our comments)|
|1. Passive developmental history the first year of life.||Overlaps with the diagnostic criteria for abnormal early development.|
|2. Continuous resistance to and avoidance of everyday demands.||Do not overlap.|
|3. Superficial sociality, but obviously lacking in social identity, pride and shame.||Overlaps. Problems related to the self and self-referring emotions are associated with ASD in general (Hobson & Hobson, 2013). Nor is socialism considered longer as unusual in the group with ASD, and the Norwegian project “Project Weather” found that over 70% cut at least “something” on sociality (Martinsen et al., 2016).|
|4. Mood swings and impulsivity due to need for control.||Partially overlap. Problems with emotional regulation and impulsivity are not uncommon at ASD (Bradley & Isaacs, 2006; Constantine & Stewart, 2006).|
|5. Comfortable in role play and “late-like play”.||Do not overlap.|
|6. Language delay as possible result of inaction.||Overlaps. Delayed language development is common at ASD.|
|7. Forced behaviour.||Overlaps. Forced behavior is defined in the ASD diagnostic criteria.|
|8. Neurological weaknesses (ex. Motor dysregulation and clumping).||Overlaps. Neurological weaknesses are common in ASD (Ming, Brimacombe, & Wagner, 2007).|
Specific notes about “Surface sociability, but apparent lack of sense of social identity, pride, or shame” trait:
- Surface Sociability is not essential for a PDA diagnosis, see article support notes.
- Newson said all seem sociable. Not all such features are universal:
- 84% show very inappropriate behaviour and social response over and above their demand avoidance.
- 68% show aggression to others, with no sex difference.
- 60% have extreme outbursts or panic attacks.
- Eighty two per cent show little sense of status or identity in others, and 86% show no sense of pride, shame, responsibility, or identity in themselves, in addition to the lack of this sense which is implied by their demand avoidance.
- Seven out of nine were reported to (4) lack awareness of age group, social hierarchy, etc. (Gillberg et al, 2015).
- Some features in this trait seem to be non-communication issues and are actually Restricted, repetitive patterns of behaviour, interests, or activities RRBIs, e.g. Panic attacks are more suitable to lability of mood.
- Assumes that persons with PDA have coding issues due to their demand avoidance, this is in addition to coding issues with social identity/ pride/ shame. So a person with PDA has deficits in responsibility, which is separate to social identity/ pride/ shame. A need for control that drives the demand avoidance. Yet, Newson notes “Despite social awareness, behaviour is uninhibited” (p597). Social awareness includes social norms, which includes social hierarchies etc. This directly contradicts the deficits they are meant to possess. Also social manipulative demand avoidance “socially manipulative” behaviour, including subtle avoidance strategies and outrageous embarrassing acts, and an obsessive need for control, resorting to violence if thwarted” (kind of paradoxically). O’Nions et al (2018) say it is often to take advantage of rules/ norms.
- Is the proposed wording, significantly different than NAS PDA profile equivalent term: “Appears sociable, but lacks understanding.” (Green et al, 2018, p457). “Atypical interaction and confused world view. Often with extreme behaviours, like violence when angry or panic attacks.”. My proposed wording is slightly more specific, attempting to suitable explanation for the more extreme behaviours captured in this trait. My wording includes confused worldview, which is often mentioned in the descriptions for this trait and I think is the cause of the surface sociability. That could be caused by deficits in “Coding” (not processing/ making sense of certain aspects of communication) deficits. Yet, it is not clear if PDA has any actual coding issues. A person can lack understanding in surface sociability, from other reasons. Social communication issues are common in mental health disorders (Wilkinson, 2016), which is a reason why social communication interventions are widely practiced outside of autism, such as with Attachment Disorder, ADHD, ODD and Conduct Disorder (CD).
- Newson used DSM-4 definitions for Pervasive Developmental Disorders (Newson et al, 2003). Phil Christie uses definitions from DSM-4 and ICD-10 (Christie, 2019). There are:
- Pervasive suggests that the effects can be seen in all a child’s development.
- Developmental means that the disorder is present at birth, gradually becoming apparent during the course of development.
- Disorder implies more than straightforward delay (Christie 2019).
These seem circular, e.g. becoming apparent as a person develops. There is nothing in these definitions that suggests a person with a PDD requires having “Coding” issues. Newson herself argues it helpful to think that any person with a PDD has Coding issues (Newson et al, 2003). Newson essentially is still viewing PDA as her “Pervasive Developmental Coding Disorder”. Vitally, PDA literature viewed non-autism conditions of ADHD, dyslexia and dyspraxia are part of the autism spectrum (Trundle et al, 2017).
- A study with 11 Revised PDA Diagnostic Interview for Social and Communication Disorders (DISCO) question indicates 44% drop off rate in persons meeting clinical threshold for PDA, as a person ages. 4 out of 11 DISCO questions are for “Surface sociability, but lack of sense of identity, pride or shame.” (O’Nions et al, 2016, p415). Some EDA-Q studies also have a decrease in PDA behaviours as a Children and Young Persons (CYP) ages. The EDA-Q has “insensitivity to hierarchy/ praise/need to manage reputation (6 items); lack of responsibility (3 items)” (O’Nions et al, 2014, p759), i.e. 9 out of 30 candidate items assess Coding issues in hierarchy/ pride/ need to manage reputation and responsibility. Coding issues are over represented in the EDA-Q and 11 Revised PDA DISCO questions; it is likely that decrease in PDA behaviours a person ages is linked to improvements in their social understanding. This supports Newson’s clinical observations of improvements in this trait (Newson et al, 2003). It does raise the questions, is the Surface Sociability trait, developmentally stable? Is it actually pervasive in PDA?
- “Failure to code social identity and hence social obligation???” (Newson, 1986), is Newson questioning what is PDA’s coding issues. “Paradoxically, examples suggest social insight sufficient to use targeted social manipulation, but a lack of awareness of social hierarchy (e.g., own/others’ age or status), and no concern for own reputation.” (O’Nions et al, 2015). O’Nions and colleagues questioning the nature of “Coding” issues in PDA. Socially manipulative demand avoidance was universal in Newson’s descriptions (Newson et al, 2020).
- “In PDA, the nature of manipulative acts, frequency and flexibility of such behaviour, and the propensity to target specific individuals appear to suggest real manipulative intent.” (O’Nions et al, 2015). This indicates there are no coding issues in relation to theory of mind and empathy. “Despite social awareness, behaviour is uninhibited” (Newson et al, 2003, p597), in relation to knowing social norms, this would include knowing social hierarchies too. In fact some of the demand avoidance strategies require knowledge of these things in order to manipulate them. Some demand avoidance is subtle “He is very subtle and will play on mothering instincts: he is hungry, he is tired, he doesn’t feel well, he needs a drink. He is being picked on, bullied, made to do things he shouldn’t do by other children”).” (O’Nions et al, 2015). It also contradicts O’Nions et al (2018) interpretation that social demand avoidance is strategic in PDA… The point is that in order to display some of the demand avoidance strategies and other behaviours, one must have knowledge about social norms etc., because they recognised them to begin with. One can recognise something, but not fully understand it, that can be from chaotic/ confused worldviews.
- O’Nions et al (2018) coding their interview data with the 11 Revised PDA DISCO questions, which includes “Apparently Manipulative Behaviour”. The “apparently” descriptor means that behaviour cannot be viewed as manipulative. I.e. social demand avoidance behaviours are still manipulative. The wording to 11 Revised PDA DISCO questions was taken by O’Nions et al (2016), before O’Nions et al (2018). The original version of this DISCO question is “Socially manipulative behaviour to avoid demands”. So O’Nions et al (2016) appear to change the wording to “Apparently Manipulative Behaviours” based only based on their clinical opinion. Some of O’Nions et al (2016) have previously written that PDA’s social manipulative aspects make it problematic fitting PDA into autism (Gillberg et al, 2015; O’Nions et al (2015). Crucially, two other original PDA DISCO question is “Socially shocking behaviour with deliberate intent” and “Lies, cheats, steals, fantasises, causing distress to others” (Gillberg et al,2015), indicating there are no coding issues relating to Theory of Mind. If a person is displaying socially shocking behaviours with intent, then surely the person displaying these behaviours is aware they are transgressing social norms and there social hierarchies; suggesting there are no coding issues in social identity/ pride/ shame.
- Do we really want to be pathologising some features in this trait; For instance, panic attacks? Surely if someone is having panic attack, it is a sign of distress, not inappropriate behaviour. There are other features, like no concerns over fitting in and not recognising the status of adults. Are these actually negative characteristics?
- “PDA is a proposed autism subtype. Fletcher-Watson and Happe discuss how in the 1980s psychologists looked for something switched off in autism and on in non-autistic persons. In PDA, complying with others’ demands is largely off and it is switched on in other individuals. PDA’s extreme levels of demand avoidance are due to high anxiety levels, yet the book acknowledges that anxiety is comorbidity external to autism; thus, PDA is not a form of autism.” (Woods, 2019a, p689).
Newson assumes because CYP display obsessive demand avoidance, they have coding problems in addition to deficits in social identity/ pride/ shame. So a person with PDA, has three sets of deficits and it is not clear, if these deficits are meant to interact with each other, if one causes another deficit etc. The three sets of deficits are: Coding problems due to having obsessive demand avoidance; deficits in social identity/ pride/ shame; a need for control. Why is Newson assuming PDA has additional coding problems due to obsessive demand avoidance? Demand avoidance outside of PDA, like in anxiety and depression is not due to coding problems, it is often from aversive experiences or trauma.
- It is plausible that Newson gave PDA “Coding” issues due to confirmation bias. She created her Pervasive Developmental Coding Disorders diagnostic grouping in March 1986 and this was used until at least 1996 (Newson, 1996). Newson reified the PDA behaviour profile in 1988 (Newson, 1989), 2 years after she created her diagnostic grouping. If PDA did not have coding issues, it could not fit into her newly created diagnostic grouping. We know that she was questioning what the coding issues are in PDA in 1986 (Newson, 1989; 1996). It is possible that there are no coding problems in PDA.
- This is linked to other points. If PDA has enough Theory of Mind and Empathy to manipulate others by taking advantage of how systems and situations due to rules present. This indicates a high level of understanding to manipulate complex situations for their own aims. If a CYP with PDA is manipulating social roles, then surely the person must understand social hierarchy. This is rewording a previous point, but it might explain it better with this wording.
- Some behaviour is from a person being highly aroused. When a person is highly aroused, they do not process information quickly and often become less rational and emotional based cognitive processing. For example, if a person is having a panic attack, said person is unlikely to be concerned about social identities/ pride/ shame; regardless if they are autistic or not. Yet, persons with PDA are meant to be aware of their actions and the impact they have on others.
- “Prefers adults but doesn’t recognise their status.” (Newson et al, 2003, p597). I suspect CYP with PDA do this as adults are more likely to display more predictable behaviours than other CYP (from CYP with PDA’s perspective). This is probably why CYP with PDA prefer company of adults. Are adults easier to manipulate than other CYP?
- “Continues to resist and avoid ordinary demands of life” (Newson et al, 2003, p597), is PDA diagnostic trait and its titular feature. There is a contradiction in CYP having coding issues with their obsessive demand avoidance. “Seems to feel under intolerable pressure from normal expectations; devotes self to actively avoiding these.” (Newson et al, 2003, p597). For a person to feel intolerable pressure from normal expectations, one must recognise what normal expectations are, which would include social norms etc.
- Newson discusses persons with PDA displaying inappropriate behaviour; this raises the question, inappropriate from whose perspective?
- Personally, as much as I would like to split the “Surface Sociability” trait in two, removing RRBIs into other traits. Such as panic attacks into “Lability of Mood”. I would make the “Surface Sociability” trait optional to a PDA diagnosis. This makes sense considering social communication problems are common in mental health disorders and such interventions are widely practiced with such CYP, like ADHD, Attachment Disorder, CD and ODD. It is too premature to fundamentally change Newson descriptions, considering the lack of research into non-autistic populations and the predicted populations are based off Newson’s behaviour profile. For examples see Christie (2007), McElroy (2016) and Gillberg (2014). It has been predicted PDA might be as common as between 3% – 5% of the human population (Gillberg et al, 2015).
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