Prince J R, Stewart P A, Nam J M, Blair A
Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, Maryland, USA.
Appl Occup Environ Hyg. 2001 Oct;16(10):973-8. doi: 10.1080/104732201300367236.
Industrial hygienists often observe workers to determine who should be measured based on a predicted exposure level. Such evaluations are usually based on real-time observation, yet surprisingly little research has been conducted on what determinants of exposure industrial hygienists use to rank workers and whether the ranking is accurate. Accuracy of the ranking may also be affected by the observation process, which is limited when conditions in the workers' immediate environment are rapidly changing. An alternative to real-time observation is videotaping workers and evaluating the tapes at a later date. A pilot study was conducted using previously collected data to determine if workers could be ranked by exposure level utilizing a scoring system to rate videotaped work practices. Six farmers had been videotaped and their dermal exposures measured as they applied insecticide to hogs. In this study, scores were developed to rate the farmers' working conditions by exposure level. Two types of determinants were used to describe exposure: touching and work practices. Touching included the number of times parts of the body had contact with surfaces possibly contaminated with insecticide. Work practices included the types of clothing and protective equipment worn as well as specific practices used by the farmer (e.g., application method). Two raters conducted independent assessments of the videotape using the same criteria. One rater reviewed the tape twice. Agreement between the raters for the "touching" score was weak (intra-class coefficient (ICC) = 0.28), but there was excellent agreement between the two raters (ICC = 0.92) for overall quality of work practices. As expected, a greater number of touches was moderately correlated with an increase in total exposure (rs = 0.60) and there was a weak inverse relationship between protective work practices and the exposure under the clothing (rs = -0.26). All other relationships with exposure level were contrary to what was expected. Since videotapes provide the industrial hygienist with a record of work events and can capture details that might otherwise be missed or not considered they may play a useful role in exposure assessment, especially if carefully developed procedures are followed to overcome the limitations found by this pilot study.
工业卫生学家经常观察工人，根据预测的接触水平来确定哪些工人应该接受测量。此类评估通常基于实时观察，但令人惊讶的是，关于工业卫生学家用于对工人进行排名的接触决定因素以及排名是否准确，所开展的研究极少。排名的准确性也可能受到观察过程的影响，当工人直接环境中的条件迅速变化时，观察过程会受到限制。实时观察的一种替代方法是拍摄工人的录像，并在之后评估录像带。利用先前收集的数据进行了一项试点研究，以确定是否可以使用评分系统对录像的工作实践进行评级，从而按接触水平对工人进行排名。六名农民在给猪施用杀虫剂时被拍摄了录像，并测量了他们的皮肤接触情况。在这项研究中，制定了分数来按接触水平对农民的工作条件进行评级。使用了两种决定因素来描述接触情况：接触和工作实践。接触包括身体部位与可能被杀虫剂污染的表面接触的次数。工作实践包括所穿的服装和防护设备类型以及农民使用的特定实践（例如，施用方法）。两名评估人员使用相同的标准对录像带进行了独立评估。一名评估人员对录像带进行了两次审查。评估人员之间在“接触”分数上的一致性较弱（组内相关系数（ICC）= 0.28），但在工作实践的总体质量方面，两名评估人员之间的一致性非常好（ICC = 0.92）。正如预期的那样，更多的接触次数与总接触量的增加呈中度相关（rs = 0.60），并且防护工作实践与衣服下的接触之间存在微弱的负相关关系（rs = -0.26）。所有其他与接触水平的关系都与预期相反。由于录像带为工业卫生学家提供了工作事件的记录，并且可以捕捉到否则可能会被遗漏或未被考虑的细节，因此它们可能在接触评估中发挥有用的作用，特别是如果遵循精心制定的程序来克服本试点研究中发现的局限性。
