Effects Job Rotation in the Prevention of Work Related Musculoskeletal Disorders: Cluster Randomized Trial

This study is single-blinded RCT, whose aim is to evaluate the effect of the rotation function in the prevention of musculoskeletal disorders in industrial workers Methods: Participants will be recruited from employees a textile industry. The inclusion criteria are: employees age between 18 and 65 years and be able to read and understand the questionnaires. The number of working hours lost due to leave for sick leave due to illness of the musculoskeletal system and connective tissue (M Group International Classification of Diseases, ICD-10) is used to estimate the sample size. The average time lost during the last three months, in companies where the study was conducted is approximately 1,100 hours. Assume that interventions will enable a reduction of this number by 10%, ie, the groups will have a difference of 100 lost working hours, with a standard deviation of 250 hours. Will be considered a statistical power of 80%, α=0.05 and a follow-up loss of up to 15%. Thus, 116 workers are required per group. The productive sectors included in the study will be pre- stratified from the level of exposure to ergonomic risk factors. The sectors with similar demands will be grouped and randomly divided between the intervention group and the control group. The intervention group will perform rotation function, switching between tasks with low, moderate and high ergonomic risk and different requests for ergonomic body region added to ergonomic guidelines. The control group will receive only the ergonomic guidelines. Primary outcomes: Absence from work due to sick leave due to disease of the musculoskeletal system and connective tissue. Secondary outcomes are: musculoskeletal symptoms (Nordic Questionnaire and EVA), ergonomic risk factors (Quick exposure Check and Job Factors Questionnaire), psychosocial factors and fatigue (Need for Recovery Scale (NFR), general health status (WHOQOL-bref), physical activity level (Baecke Questionnaire), productivity with Work Performance Questionnaire (HPQ) and costs (incremental cost effectiveness ratio). Outcomes will be assessed at baseline and after 3 , 6 and 12 months . The information on the amount of hours lost by removal for medical leave will be recorded daily. Expected results: It is expected that interventions to reduce the occurrence of musculoskeletal disorders and consequent worker absenteeism due to sick leave, 100 hours of work lost. It is expected that the results obtained in this study may contribute to setting standards in the field of Occupational Health, as well as for decision making of professionals working in this area.