Impact of ergonomic training on musculoskeletal health in manufacturing assembly line workers

Thesis Abstract

Manufacturing assembly line workers are increasingly susceptible to musculoskeletal disorders (MSDs) due to prolonged repetitive tasks and suboptimal ergonomic practices, which compromise workers’ health and productivity. This study seeks to evaluate the impact of structured ergonomic training interventions on the prevalence and severity of musculoskeletal complaints among assembly line personnel in a large manufacturing firm. The primary aim is to determine whether targeted ergonomic education can significantly improve workers’ musculoskeletal health and reduce injury-related absenteeism. The specific objectives include assessing baseline ergonomic awareness, measuring changes in posture and work behavior post-intervention, and evaluating the correlation between ergonomic improvements and reported MSD symptoms over a six-month follow-up period. Employing a mixed-methods research design, the study integrates quantitative and qualitative approaches to obtain a comprehensive understanding of the intervention’s effects. The quantitative component adopts a quasi-experimental pre-test/post-test control group design, with a sample size of 200 assembly line workers selected through stratified random sampling from a manufacturing plant employing 500 workers. The control group (n=100) receives no ergonomic training initially, while the experimental group (n=100) undergoes a four-week ergonomic training program based on the Job Accommodation Network (JAN) guidelines, emphasizing correct posture, equipment adjustment, and safe working practices. Data collection instruments include the Nordic Musculoskeletal Questionnaire (NMQ), ergonomic knowledge questionnaires, and observational checklists. Qualitative data derive from focus group discussions and in-depth interviews with participants to explore perceptions of ergonomic training effectiveness. Validity and reliability of the instruments are ensured through pilot testing, expert validation, and internal consistency analysis (Cronbach’s alpha exceeding 0.85). Data analysis involves descriptive statistics (means, standard deviations), inferential techniques including paired t-tests to compare pre- and post-intervention scores, and multiple regression analysis to identify predictors of musculoskeletal complaints. Thematic analysis is employed to interpret qualitative data, providing nuanced insights into participant experiences. Furthermore, a framework based on the Theory of Planned Behavior underpins the analysis of behavioral change related to ergonomic practices. It is anticipated that ergonomic training will lead to statistically significant reductions in self-reported MSD symptoms, improvements in ergonomic knowledge scores, and observable positive changes in work postures and behaviors among the experimental group compared to controls. The findings are expected to underscore the importance of ergonomic education in mitigating occupational health risks and improving working conditions. The study aims to contribute to existing knowledge by demonstrating the measurable benefits of case-specific ergonomic training programs within manufacturing settings, filling a notable gap in empirical evidence regarding long-term health outcomes resulting from such interventions. The main conclusion underscores that targeted ergonomic training is an effective strategy for reducing musculoskeletal disorders among assembly line workers, thereby enhancing occupational health and safety. Recommendations include integrating ergonomic education into standard occupational health protocols, providing periodic refresher training sessions, and adopting ergonomic assessment tools as routine workplace practices. The study suggests avenues for future research, such as longitudinal studies to evaluate sustained behavioral change and the development of industry-specific ergonomic guidelines tailored to various manufacturing sectors. Ultimately, the research affirms that proactive ergonomic education is vital for fostering healthier, more productive workforce environments in manufacturing industries.