Efficacy of the revised NIOSH lifting equation to predict risk of low back pain due to manual lifting: expanded cross-sectional analysis.

Abstract

To evaluate whether the Revised NIOSH Lifting Equation (RNLE) is a valid tool for assessing risk of low back pain (LBP) due to manual lifting by using combined data from two cross-sectional studies of 1-year prevalence. Results from a symptom and occupational history questionnaire and RNLE analysis for 677 subjects employed in 125 manual lifting jobs at nine industrial sites were combined from two studies. The odds of LBP increased as the lifting index (LI) increased from 1.0 to 3.0. A statistically significant odds ratio (OR) was found for both the 1 < LI ≤ 2 (OR = 1.81) and the 2 < LI ≤ 3 categories (OR = 2.26). For jobs with an LI value greater than 3.0, however, the OR remained nonsignificant. The 2 < LI ≤ 3 group remained statistically significant after adjusting for age, gender, body mass index, and psychosocial factors. It is clear that as the LI increases, the risk of LBP increases. Longitudinal studies are needed.