Table 1

Demographic data of patient groups

Group n Male/ female Age
(mean SD) (y)
Normal controls189/934 (10)
Neurological controls:
 Peripheral neuropathy3
 Motor neuron disease2
 Sciatica4
 Spinal stenosis2
 Back pain2
 Disc prolapse1
 Headache1
 Mechanical nerve root damage1
 Sleep disorder3
 Vertebrobasilar ischaemia1
Total209/1153 (15)
Depression4619/2753 (16)