Temporal variations in the distribution of self-harm episodes and methods across the Australian asylum seeker population: An observational study

Author summaryWhy was this study done? Research indicates that the mental health of asylum seekers is affected by stressors experienced before, during, and after the migration process; however, until recently, little has been known about self-harm among asylum seekers, due to the lack of accessible data. Research in 2019 has shown that rates of self-harm among people seeking asylum in Australia, including those on the Pacific island nation of Nauru and Manus Island (Papua New Guinea), are exceptionally high compared with the general Australian community. This research tells us about the extent of self-harm in asylum seekers, but it does not tell us anything about the timing of these self-harm episodes. Information about when self-harm occurs might highlight particular stressors, including those related to policies, practices, or the environment, which could then be targeted to reduce self-harm in future. What did the researchers do and find? We examined all self-harm incidents that were reported as occurring in the Australian asylum seeker population from 1 August 2014 to 31 July 2015, obtained via Freedom of Information ( = 949). Time of day, day of the week, and month of the year were investigated in all 949 incidents, according to the five detained and community-based asylum seeker populations in Australia (including Nauru and Manus Island). Significant variations in the distribution of self-harm over the 24-hour cycle were observed across some asylum seeker populations. While for the entire asylum seeker population there were no significant variations in rates of self-harm by month of the year, self-harm was significantly more likely to occur in August 2014 (than other months of the year) among asylum seekers in onshore detention (19%), in January 2015 on Manus Island (18%), and in October 2014 on Nauru (15%). Compared with all other methods, self-poisoning (by medication) (25%) was significantly more likely to occur between 12:00 AM and 3:59 AM, and self-battery (42%) between 8:00 AM and 11:59 AM. What do these findings mean? In this study, we observed that self-harm varied according to time of day and month of the year, including by the different asylum seeker populations. Future research should examine these temporal trends in further detail, in order to inform self-harm prevention strategies, including those at the policy level. Ongoing self-harm monitoring practices should be established to more closely track and identify temporal (and other) trends, in order to protect asylum seekers from further harm. Background Temporal patterns in the frequency and characteristics of self-harm episodes across the Australian asylum seeker population may have implications for self-harm prevention and public health policy. The aim of this study was to examine how the distribution of self-harm episodes and method(s) of self-harm used across the Australian asylum seeker population vary according to the 24-hour cycle, day, and month, and to establish a basis for further research. Methods and findings We conducted an observational study of all 949 self-harm incidents reported across the Australian asylum seeker population (representing a monthly average of 28,992 adults) between 1 August 2014 and 31 July 2015, obtained by Freedom of Information (FOI) from the Department of Immigration. Time of self-harm, day, and month of occurrence were investigated across all five Australian asylum seeker populations (i.e., community-based arrangements, community detention, onshore immigration detention, offshore immigration detention [Nauru], and offshore immigration detention [Manus Island]). Significant variations in distributions over the 24-hour cycle were observed by processing arrangements. Compared with the average distribution across all other processing arrangements, self-harm more commonly occurred among community-based asylum seekers (36.3%) between 12:00 AM and 3:59 AM (p< 0.001), in asylum seekers on Manus Island (36.4%) between 4:00 PM and 7:59 PM (p= 0.02), and among asylum seekers in onshore detention (20.4%) between 8:00 PM and 11:59 PM (p< 0.001). Compared with the average distribution across all other methods, self-poisoning (by medication) (25%) was significantly more likely to occur between 12:00 AM and 3:59 AM (p= 0.009), and self-battery (42%) between 8:00 AM and 11:59 AM (p< 0.001). The highest and lowest monthly self-harm episode rates for the whole asylum seeker population were in August (2014) (5 episodes per 1,000 asylum seekers; 95% confidence interval [CI] 1-11) and in both January and February (2015) (2.1 episodes per 1,000 asylum seekers; 95% CI 0.6-7.2), respectively; however, the overlapping CIs indicate no statistically significant differences across the months. When examining monthly trends by processing arrangements, we observed that self-harm was significantly more likely to occur in August (2014) than other months of the year among asylum seekers in onshore detention (19%) (p< 0.001), in January (2015) on Manus Island (18%) (p= 0.002), and in October (2014) on Nauru (15%) (p< 0.001). The main study limitations were that we could not investigate certain characteristics associated with self-harm (e.g., gender, country of origin), as the Department of Immigration did not routinely collect such data. There was also the potential risk of making a type 1 error, given the exploratory nature of the comparisons we undertook; we minimised this by lowering our significance threshold from 0.05 to 0.01. Conclusions Self-harm in the Australian asylum seeker population was found to vary according to time of day and month of the year, by processing arrangements. A series of procedure-related and detention-related factors were observed to be associated with the temporal variations in self-harm. These findings should form the basis for further investigation into temporal variations in self-harm among asylum seekers, which may in turn lead to effective self-harm prevention strategies.