A Systematic Review of Pathological Demand Avoidance (PDA): A Veritable Diagnosis or a Case of Circular Logic?

To assess the current level of evidence supporting the distinct diagnosis of PDA by evaluating the use of the diagnostic tools currently available.

A comprehensive search of three bibliographic databases was undertaken, including: MEDLINE, EMBASE, and PSYCHINFO. Study selection, extraction and quality assessment were conducted independently by two reviewers via Covidence. English-language studies pertaining to the diagnosis of PDA with empirical data were included. Methodological bias was critically appraised using the QUADRAS-2.

12 relevant studies were identified, nine in paediatric populations, two in adults and one in a mixed cohort. Data was usually collected via self-reported questionnaires or surveys. Two diagnostic tools were identified- the EDA-Q and the DISCO although the use of these was inconsistent. Cross-over with other conditions was also noted. Studies were all assessed as being high risk for methodological bias.

There was considerable inconsistency in the way PDA was identified across studies with a large proportion of studies relying on subjective rather than objective measures. The methodological bias inherent to these studies raises the issue of circular logic and makes it difficult to support any of the diagnostic tools pertaining to PDA, let alone the condition itself.