Background: A new self-administered questionnaire as an outcome measure for patients with cervical myelopathy was drawn up in Part 1 (Japanese Orthopaedic Association Cervical Myelopathy Evaluation Questionnaire, JOACMEQ). Because a question with regard to driving a car (C-41) was not suitable for this patient group, the authors composed an alternative question related to neck motion (C-41-2). The purposes of the present study were to perform a secondary survey on patients with cervical myelopathy and to statistically analyze the responses to validate the JOACMEQ, and also to determine if it was possible to convert item C-41 to the alternative question.
Methods: A member of the Subcommittee on Low Back Pain and Cervical Myelopathy Evaluation from each hospital administered the questionnaire to more than 50 patients with cervical myelopathy in each hospital. The questionnaire consisted of 25 questions, 24 of which were extracted in the primary survey. The authors statistically examined whether it was possible to convert question C-41 to C-41-2.
Results: Three hundred and sixty-eight patients with cervical myelopathy were enrolled in the present study. No questions elicited no answer or "I am not sure" in more than 5% of patients except question C-41. There were no questions that the patients answered with difficulty. There was no tendency that was concentrated on one option as an answer to questions. There was a high correlation between questions C-41 and C-41-2. Spearman's correlation coefficient and kappa value showed that there was high coincidence between the two questions C-41 and C-41-2. It is possible to convert the question C-41 to the alternative question C41-2.
Conclusion: The questionnaire has sufficient reliability for clinical use. It is possible that the JOACMEQ will prevail and become a global standard to evaluate outcomes in patients with cervical myelopathy.