These data provide both validation and st and ards for other users and indicate the power of the instrument for detecting change in sample population s. CONCLUSIONS The  ODI  remains a valid and vigorous measure and has been a worthwhile outcome measure .
The behavior of the instrument is incompletely understood , particularly in sensitivity to real change
STUDY DESIGN The Oswestry Disability Index ( ODI ) has become one of the principal condition-specific outcome measures used in the management of spinal disorders .
This review is based on publications using the ODI identified from the authors ' personal data bases , the Science Citation Index , and h and search es of Spine and current textbooks of spinal disorders .
OBJECTIVES To review the versions of this instrument , document methods by which it has been vali date d , collate data from scores found in normal and back pain population s , provide curves for power calculations in studies using the ODI , and maintain the ODI as a gold st and ard outcome measure .
SUMMARY OF BACKGROUND DATA It has now been 20 years since its original publication .
More than 200 citations exist in the Science Citation Index .
Lumbar spinal stenosis: a matched-pair study of operated and non-operated patients.
The prevailing opinion seems to accept that the natural course of lumbar spinal stenosis is one of progressive worsening , and that only surgery can check this development . In fact , the choice of treatment for lumbar spinal stenosis is still an open question . The aim of this study was to compare in the matched-pair format the outcome of  surgically and non-surgically treated patients with lumbar spinal stenosis . The  surgically treated group consisted of 496 patients who were operated on during the period 1974 - 1987 and 440 of whom were re-examined an average of 4.1 years after surgery . The non-surgically treated group consisted of 57 patients who were treated conservatively during the period 1980 - 1987 and were re-examined an average of 4.3 years after the start of treatment . The matching criteria were sex , age , myelographic findings , major symptom and duration of symptoms . We were able to form 54 similar matched-pairs from the surgically and non-surgically treated patients . Subjective disability was assessed using the Oswestry question naire and functional status was evaluated during the clinical examination . For statistical analysis the McNemar test and the paired Student 's t-test were used . The overall results showed no statistical difference in outcome between the matched-pair groups , but the operated men fared significantly better than the non-operated men . The functional status was very good in both groups and for both sexes . In conclusion , conservative treatment of lumbar spinal stenosis should be considered for the patients with moderate stenosis . Controlled , prospect i ve and r and omized trials are needed to clarify better the choice of treatment in patients with lumbar stenosis
These data provide both validation and st and ards for other users and indicate the power of the instrument for detecting change in sample population s. CONCLUSIONS The  ODI  remains a valid and vigorous measure and has been a worthwhile outcome measure .
The behavior of the instrument is incompletely understood , particularly in sensitivity to real change
STUDY DESIGN The Oswestry Disability Index ( ODI ) has become one of the principal condition-specific outcome measures used in the management of spinal disorders .
This review is based on publications using the ODI identified from the authors ' personal data bases , the Science Citation Index , and h and search es of Spine and current textbooks of spinal disorders .
OBJECTIVES To review the versions of this instrument , document methods by which it has been vali date d , collate data from scores found in normal and back pain population s , provide curves for power calculations in studies using the ODI , and maintain the ODI as a gold st and ard outcome measure .
SUMMARY OF BACKGROUND DATA It has now been 20 years since its original publication .
More than 200 citations exist in the Science Citation Index .