Using the Benefit-Harm Trade-off Method to Determine the Smallest Worthwhile Effect of Intensive Motor Training on Strength for People with Spinal Cord Injury

Study design Interviews using the benefit-harm trade-off method and an online survey.Objectives To determine the smallest worthwhile effect (SWE) of motor training on strength for people with spinal cord injury (SCI).Setting SCI units, Australia.Methods Forty people with recent SCI who had participated in motor training as part of their rehabilitation program (patient participants) and 37 physiotherapists (physiotherapist participants) working in SCI were recruited. The patient participants underwent an iterative process using the benefit-harm trade-off method to determine the SWE of motor training on strength. The physiotherapist participants were given an online survey to determine the SWE for five different scenarios. Both groups considered the SWE of a physiotherapy intervention involving an additional 12 h of motor training for 10 weeks on top of usual care. They were required to estimate the smallest improvement in strength (points on the Total Motor Score of the International Standards for Neurological Classification of SCI) to justify the effort and associated costs, risks or inconveniences of the motor training.Results The median (interquartile range) smallest improvement in strength that patient and physiotherapist participants deemed worth the effort and associated costs, risks or inconveniences of the motor training was 3 (1-5) points, and 9 (7-13) points, respectively.Conclusions People with recent SCI are willing to devote 12 h a week for 10 weeks to motor training in addition to their usual care to gain small changes in strength. Physiotherapists wanted to see greater improvements to justify the intervention.