de Zwart B C, Broersen J P, van der Beek A J, Frings-Dresen M H, Van Dijk F J
Coronel Institute for Occupational and Environmental Health, Academic Medical Center, University of Amsterdam, The Netherlands.
Occup Environ Med. 1997 Nov;54(11):800-6. doi: 10.1136/oem.54.11.800.
To (a) describe differences in the outcome of cross sectional and longitudinal analysis on musculoskeletal complaints relative to age and work demands, and (b) to assess the entrance and drop out selection on musculoskeletal complaints among groups of employees relative to age and work demands.
A study population was selected on the basis of questionnaire data from periodical occupational health surveys of almost 45,000 employees collected between 1982 and 1993. From all companies within this data base that participated twice in company wide surveys four years apart, male employees were selected, and stratified for age and work demands. There were several populations: follow up (participation in both surveys); drop out (participation only in the first survey); entrance (participation only at the second survey); and two cross sectional populations (all participants at each survey). Prevalences of back complaints and turnover rates were analysed.
Reported back complaints in the cross sectional analysis declined over the oldest age groups in heavy physical work versus a small increase in the longitudinal analysis. The age group 50-9 and back complaints were identified as predictors at the first survey for not participating at the second survey. Neither age nor work demands at the first survey indicated drop out among those employees with back complaints at the first survey. The effects of entrance selection on estimated prevalences were small.
The results indicate that musculoskeletal disorders lead to selection out of work, affecting the validity of both cross sectional and longitudinal epidemiological studies. In future studies analyses of turnover figures on musculoskeletal complaints relative to work demands and age are recommended.
(a) 描述肌肉骨骼疾病横断面分析和纵向分析在结果上相对于年龄和工作要求的差异，以及 (b) 评估员工群体中肌肉骨骼疾病在相对于年龄和工作要求方面的入选和退出情况。
根据1982年至1993年期间对近45,000名员工进行的定期职业健康调查的问卷数据选择研究人群。从该数据库中两次间隔四年参与全公司范围调查的所有公司中，挑选男性员工，并按年龄和工作要求进行分层。有几类人群：随访组（两次调查均参与）；退出组（仅参与第一次调查）；新入选组（仅参与第二次调查）；以及两个横断面人群（每次调查的所有参与者）。分析了背部疾病的患病率和人员更替率。
在横断面分析中，从事重体力劳动的最年长年龄组报告的背部疾病有所下降，而纵向分析中则略有增加。50 - 59岁年龄组和背部疾病被确定为第一次调查时不参与第二次调查的预测因素。第一次调查时的年龄和工作要求均未表明第一次调查时有背部疾病的员工会退出。新入选情况对估计患病率的影响较小。
结果表明，肌肉骨骼疾病会导致员工离职，影响横断面和纵向流行病学研究的有效性。建议在未来研究中分析与工作要求和年龄相关的肌肉骨骼疾病人员更替数据。
