Objectives: For diagnosing neuropathic pain, a simple 6-item patient-completed identification pain questionnaire has been validated among Caucasians. We aimed to study the validity and reliability of this questionnaire among Hong Kong Chinese patients.
Design: Questionnaire survey.
Setting: Two pain clinics and two neurology clinics in Hong Kong.
Patients: Patients with either neuropathic pain or nociceptive pain were recruited randomly from the four clinics. The patients completed the questionnaire themselves and the diagnosis of neuropathic pain and nociceptive pain was made by the pain specialists. We determined the optimal cutoff, positive and negative predictive values, sensitivity, specificity, the area under the receiver operating characteristic curve, and test-retest reliability of the translated version.
Results: Among the 92 participants, 60 (65%) had neuropathic pain and 32 (35%) had nociceptive pain. At an optimal cutoff score of 3 or higher, the positive predictive value was 87% while the negative predictive value was 55%, and it correctly classified 71% of cases. The specificity and sensitivity were 81% and 65%, respectively. The area under the curve was 0.78 (P<0.001). Test-retest reliability in the 10 randomly selected patients showed a good intraclass correlation of 0.72.
Conclusion: The Chinese Identification Pain Questionnaire is a valid and reliable scale that may be used as an initial diagnostic tool for neuropathic pain among Hong Kong Chinese patients.