Cost-Effectiveness of a Multi-faceted Workplace Intervention to Reduce Musculoskeletal Pain in Nursing Staff: A Cluster-Randomized Controlled Trial (INTEVAL_Spain)

PurposeTo evaluate the cost-effectiveness of a multifaceted workplace intervention to reduce musculoskeletal pain (MSP) in nursing staff.MethodsThe study was a 1-year cluster-randomized controlled trial. The intervention combined participatory ergonomics, health promotion, and case management. The control group received usual care. Societal and health system perspectives were used. Costs included direct health and indirect costs. The effects were MSP and quality-adjusted life years (QALYs). MSP was measured using the Standardized Nordic Questionnaire at baseline and 6- and 12-month follow-up. QALYs were measured using the EuroQol-5D-3L at 6- and 12-month follow-up. Incremental costs and QALYs were modelled using generalized linear models. MSP was analysed through generalized logistic models. Incremental cost-effectiveness ratios (ICERs) were calculated, and cost-effectiveness planes and acceptability curves were constructed.ResultsTotal mean costs per person were <euro>614 and <euro>216 for the intervention and control group, respectively, with a societal perspective. The intervention mean cost was <euro>38/person. From the societal perspective, the ICER showed that overall additional <euro>68 (<euro>9 from a health system perspective) were required to achieve 1-extra-percentage-point reduction of MSP. ICERs were <euro>34 from the societal and <euro>4 from the health system perspectives for neck, shoulders and upper back pain; <euro>53 and <euro>7 for low back; <euro>179 and <euro>23 for hands; <euro>39 and <euro>5 for legs; <euro>115 and <euro>14 for the knees; <euro>36 and <euro>5 for feet For MSP in the elbows. For participants with pain in the elbow, and for QALYs, the ICER showed that the intervention group was dominated by the control group.ConclusionThis intervention was not cost-effective in terms of QALYs. However, in terms of MSP, with a willingness to pay of <euro>100, the probability of the intervention being cost-effective was around 90%. Further studies incorporating our recommendations are needed to confirm these findings.Study RegistrationISRCTN15780649, retrospectively registered.