Extreme Demand Avoidance 8-item measure (EDA-8)


In 2013, Dr Liz O’Nions et al developed the Extreme Demand Avoidance Questionnaire (EDA-Q) to measure caregiver reported behaviours in clinical accounts of extreme/‘pathological’ demand avoidance in Autistic children and young people aged 5-17.  This questionnaire sought to measure these traits consistently for research purposes, but was not designed to be a diagnostic test.

In 2021, O’Nions et al further refined the EDA-Q to provide a caregiver report measure of 8 items, the EDA-8. The items dropped from the EDA-Q were those which showed less consistency with child age, gender, ability or independence. The items retained were found to cover the features consistently described in accounts of PDA. The EDA-8 is designed for research purposes and has not been tested in clinical settings.

  • The English version of the EDA-8 can be downloaded here.
  • The Norwegian version* of the EDA-8 (translated by Torill Fjæran-Granum) can be downloaded here.
  • The Spanish version* of the EDA-8 (translated by Rocio Manzanera Lidon) can be downloaded here.
  • The Finnish version* of the EDA-8 (translated by Autism Finland) can be downloaded here.
  • The 2021 study describing the refinement of the EDA-8 can be found here.
  • The original article describing development of the EDA-Q can be found here.


No clinician-rated instrument for identifying a PDA profile has yet been developed and tested. However, a range of tools have been developed for research purposes which can be a helpful aid for practitioners exploring a PDA profile. The EDA-8 is one such tool with other tools listed in section ‘4.3. Diagnostic Tools’ of our ‘Practice Guidance for Identifying and Assessing a PDA profile’.

The EDA-8 asks about a person’s presentation not the causation of this presentation. There are a range of reasons why a person may present with extreme demand avoidance besides PDA. Therefore, a high score on the measure does not in itself indicate a PDA profile. More in-depth assessment is needed to establish whether a PDA profile is underpinning demand avoidance behaviours. This would consider early development and take into account any situational factors affecting current behaviour.

The questionnaire is intended for use by researchers wanting to measure extreme demand avoidance traits.

*The PDA Society is not able to verify the accuracy of translations listed on our website.