Availability of lift equipment, physical workload, psychosocial job factors, and prevalence of back pain among critical-care nurses

Introduction
Use of patient lifts is an important injury prevention method for nursing personnel. However, lift equipment targets only reduction of biomechanical risks whereas work-related musculoskeletal disorders are a multifactorial problem. This study examined if there are any associations between the availability of lifts, other risk factors, and back pain prevalence among critical-care nurses in the United States.

Methods
The study sample consisted of 361 critical-care nurses who participated in a nation-wide postal survey assessing 12-month prevalence of musculoskeletal symptoms, availability of lifts, physical and psychosocial job factors, and individual factors. Back pain cases were defined as symptoms with at least moderate intensity that occurred at least monthly or lasted at least one week. Multivariable logistic regressions and 95% Confidence Intervals (CIs) were used to determine the association between variables.

Results
Seventy-six percent of the sample experienced any back pain in the past 12 months, and 27% met the case definition. Back pain was reported by 25% of nurses who had lifts on their units and 28% of nurses who did not have lifts. In a multivariable analysis adjusting for confounders, there was no significant difference in back pain prevalence by lift availability (OR=0.86, 95% CI 0.50–1.43). Back pain was significantly associated with cumulative physical workload, job strain, effort-reward imbalance, overcommitment, and safety climate, after adjustment for age, sex, race, education, body mass index, shift, and break time. The associations of back pain with job strain, effort-reward imbalance, and overcommitment remained significant after additional adjustment of cumulative physical workload.

Discussion
These study findings suggest that intervention programs solely relying on lift equipment may not be sufficient for back injury prevention. Comprehensive programs intervening simultaneously on ergonomic, psychosocial, and organizational factors are needed to protect nursing personnel.