Helpful information: supporting the use of SF-36 alone to evaluate the progress of patients with low back pain. 

The following study would appear to be helpful in evaluating the responsiveness of Oswestry Disability Index MODEMS scales and SF-36 for patients with low back/leg symptoms.

Results
This analysis of 970 patients at base line and 3 months showed 68% having a consensus improvement across the questionnaires.  The scales with the highest probabilities of correctly identifying patient’s improvement were the condition specific pain scale from MODEMS; the general pain scale from SF-36; the combined pain and function scale from SF-36; the condition specific function measure from the Oswestry and the physical function measure from the SF-36.

Conclusion
The conclusion of the study is that for patients with low back problems, the general SF-36 maybe a sufficient measure of health status and patient function without the need for additional condition specific instruments.  Pain scales appear to be most responsive measures in patients with low back pain. 

Author
Walsh, Thomas L MS, PT, OCS Dip MDT; Hanscom, Brett MS; Lurie, Jon D MD, MS; Weinstein, James N DO, MS

Title
Is a condition specific instrument for patients with low back pain/leg symptoms really necessary?  The responsiveness of the Oswestry Disability Index, MODEMS, and the SF-36. 

Source
Spine 28(6):607-615, March 15 2003.