Bao S, Howard N, Spielholz P, Silverstein B
Safety & Health Assessment & Research for Prevention Program, Washington State Department of Labor and Industries, P.O. Box 44330, Olympia, WA 98504, USA.
Ergonomics. 2007 Dec;50(12):2118-36. doi: 10.1080/00140130701458230.
This paper presents two posture risk quantification methods: first, an event-based method where the most common and the worst postures are estimated in a task; second, a time-based method where posture distributions are calculated from random samples of observed postures in the task. A 'click-on-screen' posture data entry method was developed for the time-based posture analysis method to make the observation process easier and to reduce possible posture categorization bias. Both methods were used to quantify various work posture parameters among a study cohort of 733 subjects from a prospective epidemiological study of upper extremity musculoskeletal disorders. Composite posture indices using a modified Rapid Upper Limb Assessment (RULA) method were also computed using data obtained by the two posture analysis methods. Results showed that both methods were able to distinguish jobs with large differences in certain posture measures. However, they did not produce the same results and could not be used interchangeably. Risk evaluation criteria should be developed, either for specific posture parameters or as a composite index, with a well-defined postural analysis method, so that users can follow exact procedures and obtain comparable results. The event-based method is easy to use and may suit practitioners better, while the time-based method adds more information to the measurement and may suit users who want more detailed information about posture exposure.
第一种是基于事件的方法，即在一项任务中估计最常见和最差的姿势；第二种是基于时间的方法，即根据任务中观察到的姿势的随机样本计算姿势分布。为基于时间的姿势分析方法开发了一种“屏幕点击”姿势数据录入方法，以使观察过程更轻松，并减少可能的姿势分类偏差。这两种方法都用于对来自上肢肌肉骨骼疾病前瞻性流行病学研究的733名受试者的研究队列中的各种工作姿势参数进行量化。还使用两种姿势分析方法获得的数据，采用改良的快速上肢评估（RULA）方法计算复合姿势指数。结果表明，两种方法都能够区分在某些姿势测量上有很大差异的工作。然而，它们产生的结果不同，不能互换使用。应针对特定的姿势参数或作为复合指数，开发具有明确姿势分析方法的风险评估标准，以便用户能够遵循确切的程序并获得可比的结果。基于事件的方法易于使用，可能更适合从业者，而基于时间的方法在测量中增加了更多信息，可能适合想要获得有关姿势暴露更详细信息的用户。
