Tak Sangwoo, Paquet Victor, Woskie Susan, Buchholz Bryan, Punnett Laura
Department of Work Environment, University of Massachusetts Lowell, Lowell, Massachusetts, USA.
J Occup Environ Hyg. 2009 Feb;6(2):113-20. doi: 10.1080/15459620802615822.
This study investigated sources of variance in exposure to risk factors for knee pain in a variety of highway construction trades, operations, and tasks. Over 15,000 discrete observations of leg postures and weights handled were made on 120 construction workers in five construction trades, in nine operations over 79 days. The contributions of trade, operation, task, and worker to the variability in work time spent kneeling, squatting, and carrying loads were evaluated with multilevel random effects models. Construction operation and task explained about 20% to 30% of total variation in kneeling, squatting, and carrying loads. There was a large unexplained component of variance thought to represent day-to-day variability of exposure within task. Reliable assessments of knee exposures require multiple days to accommodate the high variability of exposures among operations and tasks and over time. These sources of variability should be carefully considered in efforts to estimate exposures to knee loading for epidemiologic or intervention studies. Homogenous exposure groups are not easily defined from the readily available organizational features of construction work.
本研究调查了各类公路建设行业、作业和任务中膝关节疼痛风险因素暴露的变异来源。在79天内，对五个建筑行业的120名建筑工人进行了超过15000次腿部姿势和搬运重量的离散观察，涉及九种作业。使用多层次随机效应模型评估了行业、作业、任务和工人对跪着、蹲着和负重工作时间变异性的贡献。建筑作业和任务解释了跪着、蹲着和负重总变异的约20%至30%。存在一个很大的无法解释的变异成分，被认为代表了任务内暴露的日常变异性。膝关节暴露的可靠评估需要多天时间，以适应作业和任务之间以及不同时间暴露的高度变异性。在为流行病学或干预研究估计膝关节负荷暴露时，应仔细考虑这些变异来源。从建筑工作现有的组织特征中不容易定义同质暴露组。
