Sex Life Question on Oswestry Disability Index is Accurately Answered by Most Patients with Chronic Low Back Pain
Anecdotal evidence suggests that the sex life-related question of the Oswestry Disability Index (ODI-8) may need to be altered because it is either inaccurately answered or limits patient participation in the survey. In a new study, researchers found that while nearly half of patients with chronic low back pain did not answer ODI-8, those who did complete this question answered correctly. The authors concluded that section 8 (Figure 1) does not need to be removed or changed in the ODI.
Figure 1. An excerpt of the Oswestry Disability Index 2.0 showing section 8—sex life. Data extracted from Fairbank JC, Pynsent PB. The Oswestry Disability Index. Spine (Phila Pa 1976). 2000;25(22):2940-2952.
Why ODI-8 is Believed to be Answered Inaccurately
“It is anecdotally believed that patients often complete ODI-8 in regard to psychosocial factors rather than pain-related factors,” explained senior author Laurence A.G. Marshman, MD, FRACS, Consultant Neurosurgeon, Institute of Surgery, The Townsville Hospital, Townsville, Queensland, Australia. “For example, patients may score ODI-8 highly because they abstain from sex because they have had radiotherapy for prostate cancer, do not have a partner, etc. If sex was an option, pain may not have, in fact, actually affected it. Respondents should avoid completing ODI-8 if it is not applicable; however, many believe that respondents do not actually do this. Instead, it is believed that ODI-8 is completed incorrectly.”
“Further, it is believed that ODI-8 may actually cause complete ODI avoidance,” Dr. Marshman explained. “For example, in some cultures, sex is taboo: patients may feel inclined to decline ODI participation altogether when they see ODI-8 as they quickly scan through first. Evidence that ODI-8 is anecdotally believed to cause problems exists in the fact that multiple ODI versions without ODI-8 have been generated,” Dr. Marshman explained.
Based on the study findings, “We hope that only one ODI version will be used, and that we can all be satisfied that ODI-8 is validated. One ODI version would help to standardize all research,” Dr. Marshman said.
Half of Patients With Chronic Low Back Pain Did Not Complete ODI-8
The study was conducted at a multidisciplinary back pain clinic in Australia and included patients age 18 years and older with low back pain for at least 3 months. Of the 88 patients eligible to enroll in the study, 65 patients (age 19 to 80 years) participated.
While 34 of the 66 patients (47.7%) did not complete ODI-8, 100% of the patients completed the rest of the ODI item, suggesting that the ODI-8 does not deter participation in the overall ODI. Nonresponders were significantly older than responders (mean, 60.6 vs 47.8 years; P=0.001) and smoked significantly fewer cigarettes per day (1.9 vs 8.3; P=0.05). No other significant demographic differences were found.
Among responders, ODI-8 was correlated with prospectively identified pain-correlated questionnaire reponses (eg, Short Form-12 version 2, Short-Form McGill Pain Questionnaire–version 2, and the Fear-Avoidance Beliefs Questionnaire), but not non-pain–correlated questionnaires. Thus, ODI-8 is considered an accurate measure of pain-mediated sexual inactivity, according to the authors.
The authors also noted that 85% of the overall group completed the other questionnaires on chronic low back pain, suggesting that the low response to ODI-8 cannot be attributed to a dislike of completing questionnaires on chronic low back pain in this population.