Skip to main content
UNITED STATES DEPARTMENT OF LABOR

Evaluation of an occupational safety and health training for cannabis cultivation workers (Brown et al., 2020)

Review Guidelines

Causal Evidence Guidelines

Absence of conflict of interest.

Citation

Brown, C., Shore, E., Van Dyke, M. V., Scott, J., & Smith, R. (2020) Evaluation of an occupational safety and health training for cannabis cultivation workers. Annals of Work Exposures and Health, 64(7), 765-769. https://doi.org/10.1093/annweh/wxaa026

Highlights

  • The study's objective was to examine the impact of an occupational safety and health (OSH) training for cannabis cultivation workers on their occupational health and safety knowledge.  
  • The study used an interrupted time series design to compare cannabis cultivation workers’ perceptions and knowledge of occupational health and safety issues before and after participation in the training. Using survey data, the authors conducted statistical analyses to compare differences in outcomes. 
  • The study found no statistically significant relationships between the training and employees’ occupational health and safety knowledge outcomes. 
  • This study receives a low evidence rating. This means we are not confident that the estimated effects are attributable to OSH training; other factors are likely to have contributed. 

Intervention Examined

Occupational Safety and Health (OSH) Training for Cannabis Industry Workers

Features of the Intervention

The Center for Health, Work, & Environment (CHWE) and the Colorado Department of Public Health and Environment organized a group of stakeholders to develop a training designed to teach workers in the cannabis cultivation industry how to recognize occupational health and safety hazards. The two-day training courses were delivered mostly in-person but did include a webcast option. Training was delivered by subject matter experts from academia, government, and safety organizations. Topics addressed in the training included occupational health and safety hazards, chemical exposures, slips, trips, repetitive motion, and best practices to avoid accidents and injuries. The goal of the training was to improve worker hazard awareness and recognition as well as enhance workers' knowledge of best practices to reduce workplace accidents and injuries. 

Features of the Study

The study used an interrupted time series design to compare cannabis cultivation workers’ perceptions and knowledge of occupational health and safety issues before and after participation in the training. A total of 208 cannabis cultivation workers participated in the training. The majority of participants were male (69.4%), with an average age of 34.8 years and an average job tenure in the cannabis cultivation industry of 2.6 years. Attendees of the training were distributed across three primary job categories: senior management (18.7%), cultivation employees (57.9%), and individuals responsible for regulatory compliance (29.9%). An additional 18.7% fell into the 'other' category. The majority (81.3%) held supervisory positions at their workplace. The training participants were asked to complete a survey before and immediately after the training. The survey was designed to measure their perceptions and knowledge of a range of occupational health and safety issues in the cannabis cultivation industry. Of the 208 training participants, 107 participants completed both the pre- and post-training surveys. The authors used statistical analyses to compare the outcomes of participants before and after they participated in the training. 

Findings

Training

  • The study found no statistically significant relationships between the training and participant’s occupational health and safety knowledge. 

Considerations for Interpreting the Findings

The authors compared the outcomes of participants measured before and after they participated in the training. For these types of designs, the authors must observe outcomes for multiple periods before the intervention to rule out the possibility that participants had increasing or decreasing trends in the outcomes examined before enrollment in the program. That is, if participants who had increasing knowledge of occupational health and safety issues in the cannabis cultivation industry tended to enroll in the program, we would anticipate further increases over time, even if they didn’t participate in the program. Without knowing the trends before training enrollment, we cannot rule this out. Therefore, the study receives a low causal evidence rating. 

Causal Evidence Rating

The quality of causal evidence presented in this report is low because the authors did not account for trends in outcomes before the intervention. This means we are not confident that the estimated effects are attributable to the OSH training; other factors are likely to have contributed.  

Reviewed by CLEAR

May 2024