{'fraction_non_alphanumeric': 0.021291696238467, 'fraction_numerical': 0.014904187366926898, 'mean_word_length': 5.103896103896104, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 2, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Work demands and musculoskeletal disorders from the Spanish National Survey.

BACKGROUND
Physical demands at work remain a leading cause of work-related injuries in industrialized countries.


AIMS
To use the 2003 Spanish National Survey of Work Conditions to examine prevalence of work-related musculoskeletal disorders (MSDs) and physical load at work.


METHODS
Using a representative sample of 5236 persons from the Spanish workforce, the prevalence of carrying or lifting heavy loads, use of significant force and repetitive movements was examined among those with and without MSDs.


RESULTS
Use of significant force and carrying heavy weights decreased inversely in relation to exposure time and was always higher among those with MSD symptoms or work-related injury. For repetitive movements, prevalence increased with longer duration of exposure and was also significantly higher in those with MSD symptoms, except in the shortest duration category.


CONCLUSIONS
One-third of workers used significant force during part of their shifts, while 4% were exposed for >50% of their work shift, suggesting that 500 000 workers in Spain are at high risk of musculoskeletal injury. Moreover, repetitive movements involving >50% of the work shift affected 30% of workers. To reduce the high incidence of MSDs and work-related injury in Spain, preventive interventions should be directed at these risk factors.