Globally, studies have consistently demonstrated the harmful mental and physical health impacts of immigration detention, with high levels of distress documented among detained asylum seekers and refugees (ASR). However, the consequences of immigration detention over time on the psychological and physical health of ASR are unclear and poorly quantified.

This prospective, mixed-methods cohort study will recurrently assess and describe the health profiles of adult ASR with an experience of Australian Government-sponsored immigration detention greater than 28 days. ASR ≥18 years old released from immigration detention will be assessed at 0, 3, 6 and 12 months and annually thereafter for up to 10 years, contingent on resourcing. Five self-report scales and a structured psychiatric interview will assess the primary outcome of depression, anxiety, post-traumatic stress, pain intensity and severity, somatic symptoms, functional impairment, physical health conditions associated with detention and engagement in available treatment of this cohort. Additionally, pre-existing health records will be accessed to identify current and previous health status and assess changes in these health indices. Quantitative findings will be triangulated with a qualitative phenomenological thematic analysis of interviews to determine additional psychosocial factors associated with the outcomes.

The study protocol was approved by the Monash Health Human Research Ethics Committee (HREC/73614/MonH-2021-251322). Results will be reported at conferences, in peer-reviewed publications and to all relevant stakeholder groups.