Research Review: Value of Back Injury Prevention Training Questioned (reprint)

This article is reprinted with permission from The Ergonomics Report™, where it originally appeared on February 13, 2008.

Back injury prevention training had little impact on the incidence/prevalence of back pain and disability, according to a review performed by Martimo et al. of eleven studies.  The authors state that either the back-protecting techniques presented in training were ineffective at reducing the risk of injury or the lifting/handling methods were not properly applied by subjects.

Key findings included:

• In two papers, individuals that received training were just as likely to experience back pain or disability as those who had no intervention over a three to twelve month period
• One randomized trial demonstrated little difference between trained and untrained groups relative to back pain/disability when tracked for over one year
• Marginal training such as showing a video or brief in-house orientations were as effective in preventing low back pain as formalized back injury prevention training in three studies
• No difference in back pain/disability was seen between groups who received training only versus training/lifting equipment versus no intervention over a three to twelve month period

Among five papers that evaluated the impact of training on lifting methods and use of lifting equipment, three reported improved technique while two cited minimal/no improvement.  One report found that subjects had an increased awareness of back injury prevention but did not demonstrate lifting/handling technique improvement.

Research Method
Identification of Studies
A literature search was conducted following the Cochrane methods – a systematic approach that relies on several means of identifying relevant reports, using both electronic and manual methods.  The search focused on studies designed as randomized controlled trials (different interventions/treatments are assigned randomly to subjects) and cohort studies (an intervention/treatment is given to a group of subjects who are compared to a similar population who do not receive the intervention/treatment).   

After screening 3,611 potentially relevant studies, 101 papers were assessed in more detail.  Inclusion criteria reduced the number of potentially appropriate articles to 23 and further analysis reduced this to eleven acceptable studies.  Of the eleven papers, two random and five cohort trials were considered to have high methodological quality.

Subjects
Postal workers were the subjects in one research article while two papers involved baggage handlers.  Eight studies were conducted with nurses as participants.  Over 17,700 volunteers were involved in the eleven studies.

Study Characteristics
The trials had various types of interventions including:

• Training/ergonomic site visit versus standard video training
• Training versus lumbar support/no training versus no intervention
• Training versus exercise in space
• Training versus in-house orientation
• Training versus physical exercise/no intervention
• Training/practical feedback versus no intervention
• Training versus one instructional meeting

Training content was somewhat unique in each study (i.e., specific technique for patient transfer; safety practices when handling patients; short lever arms during lifting/minimizing weight of burden by lifting together).  The number/duration of sessions and time span of training varied (i.e., eight 45-minute sessions over eight weeks; one 3-hour session delivered once; 104 one-hour sessions over two years with an additional eight hours).  The preferred lifting techniques presented to subjects were not described.  The use of lifting aids was encouraged in five studies.  

The length of the studies spanned from eight weeks to 5.5 years.

Study outcome measurements consisted of:

• Back injury rate (disabling and non-disabling) per 1000 worker years of exposure
• Frequency of low back pain
• Prevalence of low back pain
• Self reported low back pain during past week and past year
• Number of episodes and number of days with low back pain during the past year

What This Review Means
Lifting/handling training – even when involving lifting equipment/assist devices – appears to have a limited impact on the incidence of low back pain/disability.  An effective program may need to extend to a no-lifting policy, demonstrated management commitment, and long term reinforcement of safe lifting/handling behaviors.

Article Title: Effect of training and lifting equipment for preventing back pain in lifting and handling: systematic review

Publication: British Medical Journal, 31 January 2008, http://www.bmj.com/cgi/content/full/bmj.39463.418380.BEv1?q=rss_home

Authors: K-P Martimo, J Verbeek, J Karppinen, A D Furlan, E-P Takala, P P F M Kuijer, M Jauhiainen, and E Vilkari-Juntura