Distinguishing between nociceptive and neuropathic components in chronic low back pain using behavioural evaluation and sensory examination.

This was a one time comparison. It did not test treatment, so it cannot show that a treatment works. The sample was small, 50 patients and 20 controls, and came from one London hospital. Patients continued usual pain medication. The paper says medication use did not differ between groups, but medication can still affect pain and sensory findings. During later recruitment, patients in the higher PainDETECT group were selected preferentially to balance group numbers, so the sample may not reflect ordinary clinic proportions. Many questionnaire domains were compared. The study corrected for multiple comparisons, but the large number of tests can still produce chance findings. Only 35 McGill affective pain scores were completed because of an administrative error, so that comparison was incomplete. The higher PainDETECT group was defined by symptoms, not by a confirmed nerve lesion. The paper says this may not meet formal neuropathic pain definitions.

The principal author received a Clinical Academic Training PhD fellowship grant, CDRF-10-054, from the National Institute for Health Research. Dr Howard and Professor Williams were supported by the Medical Research Council and the National Institute of Health Research Biomedical Research Centre for Mental Health at the South London and Maudsley NHS trust. The authors declared no conflicts of interest.

Do not read the higher PainDETECT scores as proof of a nerve lesion or as evidence that a neuropathic pain treatment will help. The study did not test treatment, and the higher score group was defined by symptoms rather than by a confirmed lesion.