Clinically important outcomes in low back pain

For patients with subacute or chronic low back pain, the MCIC for pain on a visual analogue scale (VAS) should at least be 20 mm and for acute low back pain it seems reasonable to suggest that the MCIC should at least be at the level of approximately 35 mm. If a numerical rating scale (NRS) is used it seems reasonable to suggest that the MCIC should at least be 3.5 and 2.5 for patients with acute and chronic low back pain, respectively. For functional disability as measured with the Roland Disability Questionnaire it seems reasonable that the MCIC should at least be 3.5 points, whereas an MCIC of at least 10 points when the Oswestry Disability Index is used. For global perceived effect, we argue that the MCIC is most appropriately defined in terms of at least 'much improved' or 'very satisfied', instead of including 'slightly improved'. Finally, we argue that, from the point of view of cost effectiveness, every day of earlier return to work is important. The exact value for the MCIC can be determined, taking into account the aim of the measurement, the initial scores, the target population and the method used to assess MCIC.