The normative score and the cut-off value of the Oswestry Disability Index (ODI).
OBJECTIVE
The Oswestry Disability Index (ODI) is one of the most common scoring systems used for patients with low back pain (LBP). Although the normative score of the ODI was reported to be 10.19 in a review article, no study has calculated the normative score after adjusting the value based on the age distribution. In addition, none of the previous studies has estimated the cut-off value which separates LBP with disability from LBP without disability. The purpose of this study was to estimate the normative score by adjusting the data for age distribution in Japan, and to determine the cut-off value which separates LBP with disability from LBP without disability.


METHODS
We conducted an internet survey on LBP using the Japanese version of the ODQ. A total of 1,200 respondents, composed of 100 males and 100 females in each age group (from the 20s to 70s), participated in this study. We also asked them to provide information about their backgrounds. We estimated the normative score after correcting for the age distribution of Japan. We also estimated the ODI of those with or without disability, the factors associated with the ODI, and the cut-off value which separates LBP with disability from LBP without disability.


RESULTS
The participants' backgrounds were similar to the national survey. The normative score of the ODI was estimated at 8.73. The ODI of the LBP with disability group was 22.07. Those with sciatica and obese subjects showed higher ODI than those without. The optimal cut-off value was estimated to be 12.


CONCLUSIONS
We defined the normative score and the cut-off value of the ODI.
Department of Orthopedic Surgery, Faculty of Medicine, The University of Tokyo, Tokyo, Japan. juichitohnosu@yahoo.co.jp
Juichi
J
Tonosu
Katsushi
K
Takeshita
Nobuhiro
N
Hara
Ko
K
Matsudaira
So
S
Kato
Kazuhiro
K
Masuda
Hirotaka
H
Chikuda
D000328:Adult; D000368:Aged; D004185:Disability Evaluation; D006233:Persons with Disabilities; D005260:Female; D006801:Humans; D007564:Japan; D017116:Low Back Pain / Q000175:diagnosis*; D008297:Male; D008875:Middle Aged; D010147:Pain Measurement; D011795:Surveys and Questionnaires