Minimal clinically important improvement response in patients with severe osteoarthritis of the knee: Short report from a survey of clinicians.

The minimal clinically important improvement (MCII) is the smallest change that signifies an important improvement. Disease severity may complicate MCII. We developed an eight-question survey examining MCII in patients with severe knee osteoarthritis (Kellgren-Lawrence grade 4). Twenty-seven of 101 clinicians completed the survey. An MCII of 20% was selected most frequently for pain, function, and patient global assessment. Clinicians were divided on responder rate, selecting 20%, 30%, and 50% equally. These findings suggest a 20% MCII may be useful in patients with severe osteoarthritis, but that there is not enough evidence to support a responder rate in this population.