Shrier Ian, Raglin John S, Levitan Emily B, Mittleman Murray A, Steele Russell J, Powell Janette
Centre for Clinical Epidemiology, Lady Davis Institute for Medical Research, Jewish General Hospital, 3755 Ch, Côte Ste-Catherine, Montréal H3T 1E2, Canada.
BMC Med Res Methodol. 2014 Jun 11;14:77. doi: 10.1186/1471-2288-14-77.
Research on psychological risk factors for injury has focused on stable traits. Our objective was to test the feasibility of a prospective longitudinal study designed to examine labile psychological states as risk factors of injury.
We measured psychological traits at baseline (mood, ways of coping and anxiety), and psychological states every day (1-item questions on anxiety, sleep, fatigue, soreness, self-confidence) before performances in Cirque du Soleil artists of the show "O". Additional questions were added once per week to better assess anxiety (20-item) and mood. Questionnaires were provided in English, French, Russian and Japanese. Injury and exposure data were extracted from electronic records that are kept as part of routine business practices.
The 43.9% (36/82) recruitment rate was more than expected. Most artists completed the baseline questionnaires in 15 min, a weekly questionnaire in <2 min and a daily questionnaire in <1 min. We improved the formatting of some questions during the study, and adapted the wording of other questions to improve clarity. There were no dropouts during the entire study, suggesting the questionnaires were appropriate in content and length. Results for sample size calculations depend on the number of artists followed and the minimal important difference in injury rates, but in general, preclude a purely prospective study with daily data collection because of the long follow-up required. However, a prospective nested case-crossover design with data collection bi-weekly and at the time of injury appears feasible.
A prospective study collecting psychological state data from subjects who train and work regularly together is feasible, but sample size calculations suggest that the optimal study design would use prospective nested case-crossover methodology.
关于损伤心理风险因素的研究主要集中在稳定特质上。我们的目标是测试一项前瞻性纵向研究的可行性，该研究旨在检验不稳定心理状态作为损伤风险因素。
我们在基线时测量心理特质（情绪、应对方式和焦虑），并在“O”秀太阳马戏团演员表演前每天测量心理状态（关于焦虑、睡眠、疲劳、酸痛、自信的单项问题）。每周额外增加一些问题以更好地评估焦虑（20项）和情绪。问卷以英语、法语、俄语和日语提供。损伤和暴露数据从作为日常业务一部分保存的电子记录中提取。
43.9%（36/82）的招募率高于预期。大多数艺术家在15分钟内完成基线问卷，在不到2分钟内完成每周问卷，在不到1分钟内完成每日问卷。我们在研究过程中改进了一些问题的格式，并调整了其他问题的措辞以提高清晰度。在整个研究过程中没有出现退出情况，这表明问卷在内容和长度上是合适的。样本量计算结果取决于随访的艺术家数量和损伤率的最小重要差异，但总体而言，由于需要长时间随访，排除了进行纯粹每日数据收集的前瞻性研究。然而，采用每两周收集一次数据并在损伤时收集数据的前瞻性巢式病例交叉设计似乎是可行的。
从定期一起训练和工作的受试者中收集心理状态数据的前瞻性研究是可行的，但样本量计算表明，最佳研究设计将采用前瞻性巢式病例交叉方法。
