Centre for Mental Health, Melbourne School of Population and Global Health, Faculty of Medicine, Dentistry and Health Sciences, The University of Melbourne, Carlton, Victoria, Australia.
Community-Minded Psychological Services, Kingsville, Melbourne, Victoria, Australia.
PLoS Med. 2020 Aug 6;17(8):e1003235. doi: 10.1371/journal.pmed.1003235. eCollection 2020 Aug.
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.
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.
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.
澳大利亚寻求庇护者群体中自残事件的频率和特征在 24 小时周期、日和月之间的时间模式可能对自残预防和公共卫生政策有影响。本研究的目的是检查澳大利亚寻求庇护者群体中自残事件的分布以及使用的自残方法如何根据 24 小时周期、日和月而变化，并为进一步的研究奠定基础。
我们对澳大利亚寻求庇护者群体中报告的所有 949 起自残事件（代表 2014 年 8 月 1 日至 2015 年 7 月 31 日期间每月平均 28992 名成年人）进行了观察性研究，这些数据是通过向移民部申请信息自由获得的。对所有五个澳大利亚寻求庇护者群体（即社区安置、社区拘留、境内移民拘留、瑙鲁境外移民拘留和马努斯岛境外移民拘留）的自残时间、日和月发生情况进行了调查。处理安排的差异显著影响了分布情况。与所有其他处理安排的平均分布相比，社区安置的寻求庇护者（36.3%）在凌晨 12 点到 3 点 59 分之间更常发生自残行为（p < 0.001），马努斯岛的寻求庇护者（36.4%）在下午 4 点到 7 点 59 分之间更常发生自残行为（p = 0.02），而境内拘留的寻求庇护者（20.4%）在晚上 8 点到 11 点 59 分之间更常发生自残行为（p < 0.001）。与所有其他方法的平均分布相比，自我用药（25%）更有可能在凌晨 12 点到 3 点 59 分之间发生（p = 0.009），而自我电击（42%）更有可能在上午 8 点到 11 点 59 分之间发生（p < 0.001）。整个寻求庇护者群体中每月自残事件发生率最高和最低的分别是 2014 年 8 月（2014 年 8 月为 5 例/1000 名寻求庇护者；95%置信区间 [CI] 1-11）和 2015 年 1 月和 2 月（2.1 例/1000 名寻求庇护者；95% CI 0.6-7.2）；然而，重叠的 CI 表明各月份之间没有统计学上的显著差异。当按处理安排逐月检查趋势时，我们发现与其他月份相比，境内拘留的寻求庇护者（19%）在 2014 年 8 月（p < 0.001）、马努斯岛的寻求庇护者（18%）在 2015 年 1 月（p = 0.002）和瑙鲁的寻求庇护者（15%）在 2014 年 10 月（p < 0.001）更有可能在 8 月发生自残行为。本研究的主要局限性在于，我们无法调查与自残相关的某些特征（如性别、原籍国），因为移民部没有例行收集此类数据。由于我们进行的比较具有探索性，因此也存在犯第一类错误的风险；我们通过将显著性阈值从 0.05 降低到 0.01 来降低这种风险。
在澳大利亚寻求庇护者群体中，自残行为根据一天中的时间和一年中的月份而有所不同，这取决于处理安排。观察到一系列与程序相关和与拘留相关的因素与自残的时间变化有关。这些发现应该为进一步调查寻求庇护者中自残的时间变化奠定基础，这可能会导致有效的自残预防策略。
