One hundred patients with complaints of low-back pain and leg pain, consistent with a diagnosis of sciatica, were evaluated. All patients had complaints for longer than 6 months and had recently undergone electrodiagnostic testing and computed tomography (CT). Correlation was made between symptoms, straight leg raising, clinical neurological deficits, electrodiagnostic and CT findings. The radiation of pain above or below the knee and pain on straight leg raising did not show a high correlation with each other or with neurological deficits or CT findings. Electrodiagnostic studies often defined a radiculopathy in patients with equivocal clinical signs. CT findings did not predict the nature of symptoms or clinical and electrodiagnostic findings. Electrodiagnostic abnormalities showed the greatest ability to predict CT abnormalities. It is concluded that in chronic sciatica patients, no single diagnostic parameter is conclusive and a combination of clinical and laboratory findings is necessary to reach a diagnosis. In addition, many assumptions, valid in patients with acute pain cannot be extrapolated to patients with chronic sciatica.