Background: Ergonomic hazards exposure is the main cause of occupational pain. The aim of this paper is to describe the prevalence of exposure to occupational physical load by occupation, in Spanish working population, and its relationship to employment conditions and sociodemographic characteristics of workers.
Methods: We used the information contained in the Spanish Job-Exposure Matrix (MatEmESp), with data between 1997 and 2005. We describe the prevalence of exposure to ergonomic hazards, we identify the occupations with the highest prevalence of exposure and we analyze its relationship to employment conditions and sociodemographic characteristics by occupation, using Spearman correlation coefficients and Scatter plots.
Results: Repetitive movements are ergonomic hazard most frequently reported (prevalence around 60%). The greater prevalence of exposure to awkward postures are given in "Bricklayers" (96%), to handling loads in "construction labourers" (89%), to repetitive movements in "graphic arts workers" (95%) and sedentary work in "administrative assistants" (98%). We found a strong relationship (p<0,001) between the prevalence of exposure to the four hazards considered, and the proportion of people with primary education by occupation (correlation coefficients -0,62 in sedentary work and between 0,59 and 0,66 in the other). Occupations with a high proportion of women and with a university studies levels ("nurses"), also has frequent exposure to handling loads (>50%).
Conclusions: In general, the prevalence of exposure to ergonomic hazards remains high in the period analyzed. Less qualified occupations usually have a higher prevalence of exposure.