Measuring low back injury risk factors in challenging work environments: an evaluation of cost and feasibility

Abstract

Background: Measuring low back injury risk factors in field research presents challenges not encountered in laboratory environments.

Methods: We compared the practical application of five measurement methods (observations, interviews, electromyography (EMG), inclinometry, and vibration monitoring) for 223 worker days in 50 heavy-industry worksites in western Canada. Data collection successes, challenges, costs, and data detail were documented for each method.

Results: Measurement success rates varied from 42.2% (seatpan accelerometer) to 99.6% (post-shift interview) of worker days assessed. Missed days for direct monitoring equipment were primarily due to explosive environments, workplace conditions likely to damage the equipment, and malfunctions. Costs per successful measurement day were lowest for interviews (approximately 23 dollars), about 10-fold higher for observations and inclinometry, and more than 20-fold higher for EMG and vibration monitoring.

Conclusions: Costs and successful field performance need to be weighed against the added data detail gained from monitoring equipment when making choices about exposure assessment techniques for epidemiological studies.