Non-participation and attrition are rarely studied despite being important methodological issues when performing post-disaster studies. A longitudinal survey of civilians exposed to the January 2015 terrorist attacks in Paris, France, was conducted 6 (Wave 1) and 18 months (Wave 2) after the attacks. We described non-participation in Wave 1 and determined the factors associated with attrition in Wave 2. Multivariate logistic regression models were used to compare participants in both waves with those who participated in the first wave only. Analyses were performed taking the following factors into account: socio-demographic characteristics, exposure to terror, peri-traumatic reactions, psychological support, perceived social support, impact on work, social and family life, and mental health disorders. Characteristics of new participants in Wave 2 were compared with participants in both waves using a chi-square test. Of the 390 persons who were eligible to participate in the survey, 190 participated in Wave 1 (participation rate: 49%). The most frequently reported reason for non-participation was to avoid being reminded of the painful event (32%, n = 34/105). In Wave 2, 67 were lost to follow-up, 141 people participated, of whom 123 participated in Wave 1 (re-participation rate: 65%) and 18 were new. Attrition in Wave 2 was associated with socio-demographic characteristics (age, French origin) and location during the attacks, but not with terror exposure or mental health disorders. Compared with those who participated in both waves, new participants declared less social and psychological support since the attacks. Attrition at 6 months was not associated with exposure to terror or mental health disorders, which indicates that any bias in future analyses on IMPACTS on mental health outcomes will be limited. Our findings suggest the importance of adapting similar surveys for people of foreign origin and of improving strategies to avoid attrition of younger people, for example by using social media, peers, and the educational environment. The present study also revealed that a high level of exposure to terror and a lack of social and psychological support after a terrorist event could impede individuals’ participation in similar surveys in the short term.

中文翻译：

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对 2015 年 1 月法国巴黎恐怖袭击中平民的不参与和自然减员进行的纵向研究。


尽管在进行灾后研究时不参与和自然减员是重要的方法论问题，但很少有人研究。 2015 年 1 月法国巴黎恐怖袭击事件发生后 6 个月（第一波）和 18 个月（第二波）对平民进行了纵向调查。我们描述了第一波中的不参与情况，并确定了与第二波中的流失相关的因素。使用多元逻辑回归模型将两波中的参与者与仅参与第一波中的参与者进行比较。进行分析时考虑了以下因素：社会人口特征、恐怖暴露、创伤后反应、心理支持、感知的社会支持、对工作、社会和家庭生活的影响以及精神健康障碍。使用卡方检验将第二波新参与者的特征与两波参与者的特征进行比较。在有资格参与调查的 390 人中，有 190 人参与了第一波（参与率：49%）。最常报告的不参与原因是避免被提醒痛苦的事件（32%，n = 34/105）。第2波中，67人失访，141人参与，其中123人参与第1波（重新参与率：65%），18人是新人。第二波中的人员流失与社会人口特征（年龄、法国血统）和袭击期间的地点有关，但与恐怖暴露或心理健康障碍无关。与参与两波浪潮的人相比，新参与者声称自袭击以来社会和心理支持较少。 6 个月时的自然减员与接触恐怖或心理健康障碍无关，这表明未来对心理健康结果影响的分析中的任何偏差都将受到限制。我们的研究结果表明，必须对外籍人士进行类似的调查，并改进避免年轻人流失的策略，例如利用社交媒体、同伴和教育环境。本研究还表明，恐怖事件发生后高度接触恐怖以及缺乏社会和心理支持可能会阻碍个人在短期内参与类似的调查。