Oswestry or Modified Oswestry: what differs and what does not
The Modified Oswestry Low Back Pain Disability Questionnaire replaces the Oswestry’s sex life section with an employment and homemaking section and is otherwise scored the same way — ten sections rated 0 to 5, doubled to a percentage — but the wording of other sections differs between printed copies, so scores from different forms should not be assumed identical.
The one structural change
Fritz and Irrgang published the modification in 2001. They replaced the sex life section with a section on employment and homemaking, because the sex life item was frequently left unanswered. The other nine sections — pain intensity, personal care, lifting, walking, sitting, standing, sleeping, social life and travelling — are carried over.
Scoring is the same
Each of the ten sections offers six statements scored 0 to 5. When all ten are completed, the raw total out of 50 is doubled to give a percentage. If a section is left blank, the raw total is divided by the number of sections completed multiplied by 5: for nine completed sections scoring 22 in total, 22 out of 45 is about 49%.
The interpretation bands published with the original 1980 questionnaire are used for both: 0 to 20% minimal disability, 20 to 40% moderate, 40 to 60% severe, 60 to 80% crippled, and above 80% bed-bound or exaggerating symptoms. Those bands come from the original questionnaire and have not been separately validated for the modified form.
Why the wording needs checking
The original 1980 questionnaire built its pain intensity section around pain medication — “I can tolerate the pain I have without having to use pain medication”. The Oswestry Disability Index in widespread use today replaced that with statements such as “I have no pain at the moment”. Clinic copies of the modified questionnaire follow either form, and they differ from one another by a few words in other sections as well.
The scoring does not change with the wording, but the response a patient chooses can. Before comparing a modified Oswestry score with a published series, check which form that series used.
Which to use
The Oswestry Disability Index has the larger evidence base in lumbar surgery and is the more comparable choice for surgical series, and its page lists published minimal clinically important differences. The modified questionnaire is common in physical therapy settings and is the better fit when the sex life item would be unwelcome or left blank, because it yields a complete ten-section score. We could not verify a published minimal clinically important difference for the modified form, so the modified page does not show one.
Where this applies
See also the full threshold database and all guides.