“A stranger in a strange world”: A quantitative and qualitative account unravelling depersonalisation and derealisation, the diagnostic journey and future recommendations

Depersonalisation derealisation disorder (DPDR) is a dissociative disorder typified by a sense of disconnection from one’s body and environment. Emerging research suggests that self-concept clarity may play a role in DPDR, potentially reflecting disruptions to self-development following adverse childhood experiences. However, both the aetiology of DPDR and qualitative accounts of the disorder remain underexplored. This mixed-methods study, comprising of one quantitative and one qualitative study, aimed to explore the lived experience of DPDR with a particular focus on the relationship between familial and non-familial adverse childhood experiences and depersonalisation/derealisation experiences and the role of self-concept clarity in the relationship. Religion and gender were also considered given their potential influence on trauma processing and identity development. In the quantitative phase, participants completed an online survey comprising measures of childhood trauma (Childhood Trauma Questionnaire Short Form), depersonalisation/derealisation (Cambridge Depersonalisation Scale; Felt Sense of Anomaly Scale), depression (Patient Health Questionnaire-8), anxiety (Generalised Anxiety Disorder-7) and self-concept clarity (Self Concept Clarity Scale). Significant correlations were observed between DPDR symptoms and multiple forms of childhood maltreatment, including familial and non-familial emotional abuse, emotional neglect, and physical neglect... Regression analyses found that these maltreatment types significantly predicted greater depersonalisation/derealisation, with no additional predictive value from gender or religion/spirituality. A mediation analysis suggested that self-concept clarity partially accounted for the association between DPDR symptoms and childhood emotional abuse, emotional neglect and physical neglect. The qualitative phase involved 10 semi-structured interviews with participants recruited from the quantitative survey who self-identified as having a DPDR diagnosis. Thematic analysis identified six themes with nine sub-themes, illustrating the profound sense of detachment associated with DPDR, its overlap with anxiety and depression, and the impact of limited professional knowledge. Overall, the study advances understanding of developmental mechanisms underlying DPDR and the possible mediating role of self-concept clarity. Moreover, frequent misattribution of DPDR symptoms and limited professional awareness contributes to challenging healthcare experiences and feelings of hopelessness which may exacerbate symptoms. Consequently, increased professional education, clearer diagnostic criteria, and improved treatment guidelines are recommended to reduce distress for individuals with DPDR.