Exposure assessment of risk factors for disorders of the back in occupational epidemiology.

This review describes methods for assessing exposure to postural load of the back in occupational epidemiologic studies. Eighty-one original articles were selected that presented information on the prevalence of back disorders in occupational groups. In 47 (58%) of these studies no data on exposure to risk factors were given. In the remaining 34 studies (42%) exposure assessment was performed by questionnaire (33%), observation (9%), and direct measurement (5%). Measures of exposure were predominantly presented at the nominal and ordinal levels. It is argued that in most epidemiologic studies on disorders of the back in occupational groups the quality of exposure data is poor. Quantitative measurement methods need to be developed for application in occupational epidemiology.