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 .
A unidimensional pain/disability measure for low-back pain syndromes
Abstract A new measure is presented , suitable for documenting severity and response to treatment in chronic low‐back pain syndromes . It is self‐administered and combines two pain and seven mobility items . These were selected from pre‐existing vali date d instruments on the basis of their sensitivity to change after treatment . Their Italian vali date d translation was adopted . The measure was administered to 32 chronic low‐back pain Italian patients , all refractory to previous conservative treatments . In most cases they presented with herniation or protrusion of 1–3 lumbar discs . Patients were treated with 3–6 sessions of autotraction over a 5‐ to 15‐day period . Scores on the scale were recorded at admission , discharge and follow‐up , 1–3 months after treatment . At discharge and at follow‐up , patients were asked if , overall , they felt improved , the same or worse . At follow‐up , 20 patients out of 32 reported overall improvement . Scalometric properties of the measure were tested using Rasch analysis . For admission and follow‐up , items followed a consistent hierarchical relationship along a unidimensional pain/disability variable , which is being called back illness . The items were not redundant , in that they spread well along a wide range of difficulty/severity . The hierarchy matched well with the expected expression of the conditions of the patients . A study was conducted on 34 chronic back pain patients , showing satisfactory test‐retest reliability . Depending on the various items , Cohen 's unweighted K ranged from 0.27 to 0.78 , with ten of the 11 items above the 0.45 level of acceptability , while intraclass correlation coefficients ranged from 0.42 to 0.89 . At follow‐up , changes in BACKILL of plus 15 % or more , with respect to admission , were consistent with patients ' reports of improvement in 19 out of 20 cases . Changes in BACKILL of less than 15 % were consistent with patients reports of being the same or worse in 11 out of 12 cases
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 .