The cost-effectiveness of motivational interviewing to activate pain support in veterans seeking compensation for musculoskeletal conditions: multisite randomised clinical trial.

objectivesWe evaluated the cost and cost-effectiveness of brief motivational interviews conducted to facilitate pain and substance use treatment.

designThis two-arm parallel group 36-week multi-site randomised pragmatic clinical trial compared the motivational interviewing for pain activation (MAPS) intervention to usual care. Cost was assessed from administrative databases and participant questionnaires. Activity limitations and quality of life were also assessed. Assessment staff were blinded to treatment group assignment.

settingEight medical centres of the US Department of Veterans Affairs (VA) in the six states in the New England region of the US.

participantsVeterans with a New England address who had filed a claim for a service-related musculoskeletal injury reported at least moderately severe pain and could be reached by telephone were invited to participate but were excluded if they were enrolled in another trial, had received more than two types of VA pain services in the prior 12 weeks or were not available for follow-up. There were 1101 participants. Cost-effectiveness was evaluated in 945 trial participants (85.8%) with at least one follow-up assessment.

interventionA 1-hour long telephone-delivered motivational interview designed to engage participants in treatment was followed by up to four 20-min follow-up sessions. PRIMARY AND SECONDARY OUTCOME MEASURES: Primary outcomes were change in pain intensity and substance use. This paper reports findings from the secondary outcomes of cost-effectiveness and quality of life for the intervention relative to usual care.

resultsThe intervention cost $300 per participant, resulted in significantly greater use of physical therapy, spinal manipulation, acupuncture and other outpatient visits, and increased the cost for the care of musculoskeletal conditions by $US1,508 (p<0.001). From the societal perspective, MAPS had no significant effect on total costs (point estimate of $US1,258 higher, p=0.52). Formal healthcare system costs accounted for only 5.8% of societal costs. Other societal costs included the value of patient time (12.8%) and lost productivity (81.4%). In the short-term, the intervention was not cost-effective over the range of credible critical values of willingness to pay for a quality-adjusted life year.

conclusionsThe intervention increased use of care for musculoskeletal services, increasing cost from the perspective of the healthcare system. There was no significant difference in cost from the societal perspective. It resulted in a slight reduction in pain but had no significant effect on preference-rated quality of life. MAPS was not cost-effective over the short 36-week time horizon of the trial, but its long-term cost-effectiveness is unknown. TRIAL REGISTRATION NUMBER: NCT04062214.