Getting back to work after a disabling injury can be a long and difficult challenge for some workers. Health care professionals including counselors, social workers, physicians, physical therapists, and case managers are interested in finding a way to identify treatment programs that make a difference in work retention.
One way to measure the results of treatment is to conduct before and after tests. These are usually surveys filled out by the patients answering questions about pain, self-care, physical function, attitude, and disability. Two of the main tools in current use include the Oswestry Disability Index (ODI) and the Short Form-36 (SF-36).
When using these assessment tools, the minimum clinical important difference (MCID) is evaluated. The MCID is defined as “the smallest change or difference in results that is beneficial and leads to a change in how the patient is treated.”
What that means is that we need assessment tools that actually measure an important change (or amount of change) as a result of treatment. If these commonly used tests don’t give us that information, then the time it takes to administer the test and calculate the results just isn’t worth it.
So, when it comes to a specific goal of getting back to work (called work retention), how well do these two tools work? What’s the minimum clinical important difference (MCID) that points to return-to-work? And does that value differ based on work status (full time, part time, or modified work schedule)?
Let’s take a look at the people who were evaluated in this study. There were just over 2,000 disabled workers who had a work-related injury resulting in disability. Treatment (operative or nonoperative) was unsuccessful in helping them achieve functional improvement and return-to-work.
Comparing test score to work status showed that neither the Oswestry Disability Index nor the Short Form-36 measured the amount of change that would predict employment a year after treatment.
Simply stated, these two tools are not responsive measures when used with workers compensation patients with chronic musculoskeletal problems. They just aren’t sensitive enough tools to measure statistically meaningful changes and should not be used to assess treatment outcomes in this group of patients.
As it turned out more than three-fourths of the group (77 per cent) did get back to work. There were enough success stories that if the measuring tools were going to be predictive, they would have shown some type of minimum clinical important difference (MCID). But they didn’t because what they were measuring wasn’t linked with the final outcome of getting back to work.
Going back and looking at the results, the authors found that this study supports what other studies have reported about factors that do predict work retention. That is, older age, female gender, and longer time out on disability are factors linked with failure to get back to work.
For now, as far as finding the best way to measure clinically important changes linked with work retention in this population, the Oswestry Disability Index and the Short Form-36 (mental and physical components) are not the tools to use. More study is needed to find a way to predict individual patient improvement that will lead to a return-to-work status as the final outcome.