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 .
Defining the minimum level of detectable change for the Roland-Morris questionnaire.
BACKGROUND AND PURPOSE The Rol and -Morris Question naire ( RMQ ) is a self-administered disability measure in which greater levels of disability are reflected by higher numbers on a 24-point scale . The RMQ has been shown to yield reliable measurements , which are valid for inferring the level of disability , and to be sensitive to change over time for groups of patients with low back pain . Little is known about the usefulness of this instrument in aiding decision making regarding individual patients . The purpose of this study was to determine the minimum level of detectable change when the RMQ is applied to individual patients . SUBJECTS The study sample consisted of 60 out patients with low back pain . METHODS The RMQ was administered at the subjects ' initial visit and again 4 to 6 weeks later . Conditional st and ard errors of measurement ( CSEMs ) were computed for initial and follow-up RMQ scores , and these values were used to estimate the minimum level of detectable change . Results . Minimum levels of detectable change at the 90 % confidence level varied from 4 to 5 RMQ points . CONCLUSION AND DISCUSSION The magnitude of CSEMs is sufficiently small to detect change in patients with initial scores in the central portion of the scale ( 4 - 20 RMQ points ) ; however , the magnitude is too large to detect improvement in patients with scores of less than 4 and deterioration in patients who have scores greater than 20
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 .