Belief Versus Fact The Effectiveness of Job Rotation as Strategy to Reduce Musculoskeletal Disorders

Belief Versus Fact The Effectiveness of Job Rotation as Strategy to Reduce Musculoskeletal Disorders

Mounting research shows that both job rotation strategies are, at best, ineffective in reducing MSDs in the workplace.

At a recent conference, this profound statement struck me: Management makes decisions mainly based on beliefs and supports those beliefs with facts. This means that decisions are made based on past patterns of success and failure, rather than on logical, definable rules and information. As safety professionals, we should pride ourselves on making data-driven decisions based on science and research. Unfortunately, some implemented programs have mixed or negative results, one being the effectiveness of job rotation as a strategy to reduce musculoskeletal disorders (MSDs) in the workplace.

Job rotation is defined as a technique that moves workers between two or more jobs in a planned manner to reduce their risk of developing a MSD. Within the hierarchy of safety controls, it is considered to be an administrative control.

There are many perceived benefits of job rotation:

  • Increases worker versatility
  • Exposes workers to different experiences and skills
  • Provides workers with a broader understanding of the entire manufacturing process
  • Provides a flexible and knowledgeable workforce
  • Reduces worker boredom and monotony
  • Enhances job satisfaction
  • Cross-trains workers
  • Reduces absenteeism
  • Improves morale
  • Improves worker retention
  • Reduces work stress and MSDs

Most of these benefits are related to worker performance, satisfaction, and versatility. But the question we should be asking is, “What’s the benefit or impact it has on worker safety?”

Job rotation is commonly believed to be an effective strategy to reduce MSDs. In fact, some safety professionals use it as their primary strategy to reduce worker exposure to forceful exertions, awkward postures, high frequencies, and vibration in the workplace. It is the core of their ergonomics program.

We can realize the benefits of job rotation if we use it correctly. Unfortunately, it’s often misused. It should be a temporary (short-term) solution until engineering controls can be put in place.

Implementing job rotation typically includes these steps:

  • Identify problematic jobs through employee surveys
  • Quantify MSDs for all jobs and assign a risk rating for each (high, moderate, or low)
  • Identify engineering controls for high-risk jobs
  • Identify jobs in the potential job rotation schedule
  • Schedule jobs to reduce back-to-back, highrisk jobs
  • Schedule jobs to reduce back-to-back, highrisk demands on the same body part areas
  • Determine best sequence of jobs
  • Determine ideal length of rotation schedule
  • Deploy job rotation schedule
  • Implement engineering controls that address high-risk jobs
  • Stop job rotation schedule

However, mounting research shows that both short- and long-term job rotation strategies are, at best, ineffective in reducing MSDs in the workplace. At worst, job rotation may even increase MSDs in the workplace.

To help safety professionals better understand the impact of job rotation strategies on reducing MSDs, I contacted several leading researchers on this topic. They were gracious to provide a summary of their work [listed in alphabetical order].

Kermit Davis, Ph.D., Associate Professor in the Department of Environmental Health at the University of Cincinnati and current President of the Human Factors and Ergonomics Society (HFES)

“In the manufacturing industry, job rotation is widely utilized as a potential control for ergonomic stressors across multiple jobs. The rotation schemes were often set up based on administration reasons (e.g., jobs in the same area or having similar seniority) and around existing break schedules. The effectiveness of these approaches is not understood and may spread the risk across more workers.”

Jack Dennerlein, Ph.D., Professor in the Department of Physical Therapy, Movement & Rehabilitation Science at Northeastern University

“In theory, job rotation seems to be a logical way to reduce physical stress on the body; however, differences in physical exposures between jobs are often small relative to the known risk, or the technique simply replaces one risk with another. The application of job rotation measures needs to incorporate many different organizational and physical factors in the workplace.”

Sean Gallagher Ph.D., Associate Professor in the Department of Industrial and Systems Engineering at Auburn University

“A recent analysis of the effects of job rotation was performed using the LiFFT risk assessment tool, developed by Auburn University. This tool is based on fatigue failure theory and its measure of estimated cumulative damage has shown strong associations with low back outcomes in epidemiological studies. The analysis looked at performing a job rotation involving a lowrisk job, a medium-risk job, and a high-risk job. Results of this analysis showed that rotating workers through these three jobs (as opposed to performing each job individually) led to an overall greater risk for the three workers involved. Exposing the low- and medium-risk workers to the highrisk job greatly increased their risk, which more than offset the slightly decreased risk for the high-risk worker. Based on our analysis, the only way to reduce overall injury risk in this scenario is to use ergonomic design principles to lower the risk of the high-risk job.”

Jay Kapellusch, Ph.D., Associate Professor and Chair of the Department of Occupational Science & Technology at the University of Wisconsin-Milwaukee

“Our NIOSH-funded study involved data pooled from three research sites and included 2,020 workers from 35 facilities in four U.S. states. Within this diverse cohort of workers, we found that job rotation was associated with significantly higher biomechanical exposures and between 25 percent and 70 percent increased likelihood of MSD prevalence. Job rotation was significantly associated with relatively worse psychosocial measures and, in particular, worse job satisfaction. These findings raise questions regarding whether job rotation, as currently practiced in workplaces, has efficacy as an approach to MSD intervention.

“While commonly used as a strategy to reduce the risk of MSDs, job rotation alone is likely not effective and might be increasing risk in many organizations and/or complicating production planning. If used, it is advised that workers not simply rotate from one high-exposure task to another, but rather rotate to tasks with differing levels of exposure or at least tasks that require different muscle groups. Each underlying task should be quantitatively assessed and controlled to ensure that the exposure from any one task is acceptable. Our study found no evidence that high exposures on one task are successfully offset by low exposures on other tasks.

“Simple approaches to injury prevention and intervention, such as job rotation, are unlikely to be effective in the long term. I encourage firms to pursue a continuous improvement approach, like quality control, where quantitative exposure measurements can be used to systematically identify and reduce physical exposures over time. This type of approach reduces workers’ compensation costs, lost time from WMSDs, and short- and long-term disability. As a bonus, the approach often encourages active participation at all levels and can lead to innovative solutions that help make the organization a great place to work even while improving the fiscal bottom line.”

W. Patrick Neumann, Ph.D., Professor in the Department of Mechanical and Industrial Engineering at Ryerson University (Toronto, Ontario, Canada)

“Job rotation is not a magic bullet to reduce musculoskeletal disorders. If your jobs include some with very high loading, then rotation may actually increase injury rates. Without meaningful differences in workload patterns job rotation will provide little muscular recovery for the employees. Rotation may, however, be a useful way to provide physiological variety at work and to reduce boredom. Used well, job rotation can help create a sense of teamwork as employees understand a larger portion of the system and it helps set the stage for group learning and innovation efforts. If you are using job rotation to overcome poor engineering and weak job design, you are probably just kidding yourself, and you are certainly not fooling your employees.”

Thanks to these experts, the knowledge we need to make data-driven decisions based on science and research is at our fingertips. Cumulatively, they found that job rotation:

  • is not a magic-bullet solution,
  • significantly increases biomechanical exposures and increases the prevalence of MSDs,
  • greatly increases MSD risk for workers exposed to low- and medium-risk jobs who transition to high-risk jobs, and
  • increases injuries in the workplace. The bottom line: to make decisions or embark on a process, we use our past experiences (beliefs) as a guide to move forward. But, when science and data prove otherwise, the trajectory should change; it’s smart business.

In closing, the most effective way to reduce MSDs in the workplace is to implement engineering controls. They will reduce worker exposure to forceful exertions, awkward postures, high frequencies, and vibration—that’s fact.

REFERENCES

Bao SS, Kapellusch JM, Merryweather AS, Thiese MS, Garg A, Hegmann KT, and Silverstein BA. (2016). Relationships between job organisational factors, biomechanical and psychosocial exposures. Ergonomics. 59(2):179-94.

Comper MLC, Dennerlein JT, Evangelista GDS, Rodrigues da Silva P, and Padula RS. (2017). Effectiveness of job rotation for preventing work-related musculoskeletal diseases: a cluster randomised controlled trial. Occup Environ Med. Aug;74(8):545-552.

Frazer MB, Norman RW, Wells RP, and Neumann PW. (2003). The effects of job rotation on the risk of reporting low back pain. Ergonomics. Jul 15;46(9):904-19.

Gallagher S, Schall MC, Sesek RF, and Huangfu R. (2017). Job Rotation as a technique for the control of MSDs: A fatigue failure perspective. Proceedings of the Human Factors and Ergonomics Society of the 61st International Annual Meeting. Austin, TX.

Gallagher S, Schall MC, Sesek RF, and Huangfu R. (2018). Assessment of job rotation effects for lifting jobs using fatigue failure analysis. Proceedings of the 20th Congress of the International Ergonomics Association. Florence, Italy.

Jorgensen M, Davis K, Kotowski S, Aedla P, and Dunning K. (2005). Characteristics of job rotation in the Midwest US manufacturing sector. Ergonomics. Dec 15;48(15):1721-33.

Padula RS, Comper MLC, Sparer EH, and Dennerlein JT. (2017). Job rotation designed to prevent musculoskeletal disorders and control risk in manufacturing industries: A systematic review. Appl Ergon. Jan;58:386-397.

Vinel A, Mehdizadeh A, Schall MC, Gallagher S, and Sesek RF. (2018). An optimization framework for job rotation to better assess the impact on overall risk. Proceedings of the Human Factors and Ergonomics Society of the 62nd International Annual Meeting. Philadelphia, PA.

This article originally appeared in the November/December 2019 issue of Occupational Health & Safety.

OH&S Digital Edition

  • OHS Magazine Digital Edition - June 2020

    June 2020

    Featuring:

    • FIRE SAFETY
      Recognizing and Mitigating Static Electricity Hazards
    • OIL & GAS
      New Gas Detection Technology
    • HEAT STRESS
      Stop Sweating Heat Stress
    • ELECTRICAL SAFETY
      Electricity is Everywhere
    View This Issue