Thread by @Richard_Autism

Studies showing PDA is seen outside of autism:
Absoud 2019.
Eaton 2018.
Egan et al 2019.
Flackhill et al 2017.
Newson et al 2003.
O’Nions et al 2014a.
O’Nions et al 2014b.
O’Nions et al 2015.
O’Nions et al 2016.
Reilly et al 2014.

"Profile of problematic behaviours not confined to autism" (@MAbsoud 2019, 8).
pdasociety.org.uk/wp-content/upl…

EDA-Q was used as part of assessment process.
Three groups: Autism, Autism + PDA, & Other (Trauma related issues).
EDA-Q detected PDA in all three groups.

EDA-Q has substantially lower dx threshold than used by the clinic to assess for PDA.

This for Eaton (2018).
Can be downloaded from here:
autism.org.uk/what-we-do/pro…

"One notable aspect of correlations with the EDA-QA and the AQ measure of ASD is that many persons scoring highly on the EDA-QA are NOT in the clinical range for ASD, and the EDA-QA is not greatly correlated with AQ scores...

... This suggests that while PDA will exist in some persons with ASD, pathological demand avoidance also exists in persons who do not meet caseness for ASD,...

... so PDA should be researched across a variety of clinical populations as an expression of general psychopathology". (Egan 2019, p4).

Egan 2019 link:
pdasociety.org.uk/wp-content/upl…

Link to article validating the EDA-QA.
link.springer.com/article/10.100…

"associations between PDA, ADHD, and conduct disorder, the latter two diagnoses of which can be linked to the environment, poor early caregiving and attachments (Kumsta et al, 2015)." (Flackhill et al 2017, p65).

"Eleven children (44%) scored above cut-off on the EDA-Q, 3 of which were diagnosed with ASD (43% of children with ASD)." N = 25. Flackhill et al (2017) are discussing Kaushik et al (2015).

Screenshot of Kaushik et al (2015) conference proceedings.

Link to Flackhill et al (2017).
ingentaconnect.com/contentone/bil…

A link to Newson et al (2003).
adc.bmj.com/content/archdi…

It is accepted that Newson et al (2003) cohort contains non-autistic persons in it.
Not all of Newson's cohort meet DSM-5 autism criteria (Eaton & Weaver 2020, p35; Soppitt 2021, p311).

https://twitter.com/Richard_Autism/status/1396016328671125508

https://twitter.com/Richard_Autism/status/1396018341870022656

"The children referred for diagnostic assessment tended to be a little “puzzling” or atypical in some way: hence their referral to a specialist clinic" (Newson et al 2003, p595).

"During the 1970s we saw a number of children who “reminded” their medical referrers of autism, but were clearly not typical of autism." (Newson et al 2003 p595).

A link to Christie (2007).
ingentaconnect.com/contentone/bil…

O'Nions (2014a) is the development of the Extreme Demand Avoidance-Questionnaire (EDA-Q) and can be accessed here:
acamh.onlinelibrary.wiley.com/doi/abs/10.111…

These two screenshots explain the rationale for their being non-autistic persons in O'Nions et al (2014a).

The above screenshots explaining the rationale for non-autistic CYP in O'Nions et al (2014a), can be found on this blog post here:
rationaldemandavoidance.com/2021/04/25/pda…

O'Nions et al (2014b) is the Exploring the behavioural profile article, which can be found here:
journals.sagepub.com/doi/pdf/10.117…

Most of the arguments for how there are non-autistic CYP in O'Nions et al (2014a) are also pertinent to O'Nions et al (2014b). There are some important differences; e.g. 2014b article was based on O'Nions masters research, 2014a is based on their PhD research

Arguments around those CYP with PDA diagnoses with an autism dx, this information is not provided. However, 25 CYP with PDA, were screened with an autism screening tool, the CAST (O'Nions et al 2014b, p540).

As this was done before O'Nions PhD research, O'Nions (2014b) data would have been collected during a time PDA was mainly diagnosed as a stand alone diagnosis.

"On the CAST (measuring autistic traits), 72% of the PDA group met the ‘at-risk’ cut off for ASD (a raw score > 14), compared to 79% of the ASD group" (O'Nions et al 2014b, p540).

More of the PDA group did not meet threshold on the CAST screening tool, than autism.
With N = 25. 1 CYP with PDA = 4%.
Thus, 28% not meeting CAST threshold could indicate 7 CYP with PDA are not autistic.

I know that some would go, Richard, 21% of autistic CYP did not meet threshold on CAST. To some extent I accept this is a good point. Yet there are important differences in the numbers.

Screening typically aim to have a false negative rate of about 25%. So the 21% of diagnosed autistic CYP, is actually within the expected error margin of the CAST. Yet, 28% of CYP with PDA is not.

Suppose we accept that 21% false negative rate of the autistic CYP, is applicable for CYP with PDA. This would still give us 2 (rounding up) CYP with PDA who are NOT autistic.

O'Nions et al (2014b) is an interesting paper, in how it details differences between autism, PDA and conduct disorder. It makes many good points, highlighting how it is problematic viewing PDA as an ASD. This is a tangent.

"PDA often come to the attention of ASD services, CAST
scores (measuring autistic traits) resembled ASD across all sub-scales...

... However, this apparent similarity may reflect endorsement of questionnaire items for different reasons in PDA and ASD groups...

... For example, endorsement of the CAST item ‘imposes routines on oneself or on others’ may reflect need for sameness in ASD but a need to control interactions in PDA." (O'Nions et al 2014b, p541).

This text from (O'Nions et al 2014b) is important as it states that similarities between PDA and autism maybe superficial, because of CYP PDA do things for different reasons compared to autistic CYP.

It means there is probably more than 2 non-autistic CYP with PDA among the 25 PDA cohort in O'Nions et al (2014b).

The remaining three should pretty quick to do.

So Number 11 out of 14 CYP with PDA in O'Nions et al (2015).

This example is important as CYP with PDA is diagnosed with attachment disorder, not autism and scores extremely low on the ADOS (an autism assessment tool).

"Parents invited to complete the interview were those with whom we were in direct contact (as opposed to
participants recruited via schools), whose children displayed particularly high levels of PDA relevant
behaviours...

... Interviews included here are the 14 examples most resembling Newson’s descriptions of PDA." (O'Nions et al 2015, p3).

The point here is this non-autistic CYP with PDA was part of a sample chosen to reflect researcher's views on PDA, including high PDA behaviours. It is difficult to argue that this non-autistic CYP with PDA is substantially different to PDA in autistic CYP.

A link to O'Nions et al (2015), An examination of the behavioural features associated with PDA using a semi-structured interview:
pdaresource.com/files/An%20exa…

Moving onto O'Nions et al (2016). Had N = 27 Persons with PDA. However, "All but one case met criteria for an ASD." p407.

Link to O'Nions et al (2016), Identifying features of ‘pathological demand avoidance’ using the DISCO.
link.springer.com/article/10.100…

The study is Reilly et al (2014), containing 4 case studies of CYP with PDA.

"In a population-based group of 85 children with epilepsy, four (5%) were identified as displaying significant symptoms of PDA, were assessed using the Extreme Demand Avoidance Questionnaire (EDA-Q) and are described in detail...

... all four had cognitive impairment (IQ < 85) and met DSM-IV-TR criteria for ADHD. Three, in addition, met criteria for ASD..." (Reilly et al 2014, p3236).

Reilly et al (2014) has one non-autistic CYP with PDA.

Link to final study in this list, Reilly et al (2014),
PDA in a population-based cohort of children with epilepsy: Four case studies:
sciencedirect.com/science/articl…

@neuroteachers I believe that is all 10 studies covered.

@threadreaderapp Please can you unroll.

Thank you in advance.