How to Use Biomechanical Job Exposure Matrices (Jem) On Job History for Musculoskeletal Disorders? Mathematical Modeling on the Example of Severe Knee Pain in Constances

Abstract

Introduction. Musculoskeletal disorders related to work might follow with a cumulative effect during working life. We aimed to develop a new model to allow to compare the accuracy of duration of work and intensity/frequency associations in application to severe knee pain. Methods. The CONSTANCES cohort is used with data from n=66553 subjects who were working at inclusion and coded. From a biomechanical job exposure matrix “JEM Constances”, intensity/frequency of heavy lifting and kneeling/squatting were used and applied to the work history in comparison to severe knee pain. An innovative model was developed and evaluated, allowing to compare the accuracy of duration of work and intensity/frequency associations. Results. The mean age is 49 years at inception with 46 percent of women. The G model developed was slightly better than regular models. In men, odds ratios of the highest quartile for the duration and low intensity were not significant for both exposures, whereas intensity/duration were for every duration. Results in women were less interpretable. Conclusion. Though increased duration increased strength of association with severe knee pain, intensity/frequency were important predictors among men. Exposure estimation along working history should have emphasis on such parameters, though other outcomes should be studied such as women.

Application of a Mathematical Method to Assess Associations Between Work Exposures and Severe Back and Hand Pain Using Job Exposure Matrices in the CONSTANCES Cohort

“…Thus, to consider life course exposure, job exposure matrices (JEMs) focused on ergonomic factors have been suggested, although it is still not perfectly clear how JEMs' exposure rating and the duration of exposure interact with each other 4,5 . To tackle this issue, a statistical modeling G has been developed to compare the precision of duration of work and intensity/frequency associations in application to knee disorders, as a simple example of degenerative disorders, with interesting results 6 . This model is based on the interaction between the total duration of the career range and the time-weighted average of the exposure level.…”

“…4,5 To tackle this issue, a statistical modeling G has been developed to compare the precision of duration of work and intensity/frequency associations in application to knee disorders, as a simple example of degenerative disorders, with interesting results. 6 This model is based on the interaction between the total duration of the career range and the time-weighted average of the exposure level.…”