Study designs of evaluations included in the review
The inclusion criteria were not defined in terms of the study design. Forty-one per cent of the included studies were prospective studies.
Specific interventions included in the review
Studies that used various history and physical examination items were eligible.
The included studies used the following diagnostic tests: presence and distribution of pain; straight leg raising (less than 60 degrees, typical Lasegue's sign, crossed straight leg); paresis (iliopsoas, tibialis anterior, gastrocnemius, extensor hallicus longus); atrophy (calf); sensory deficits; depressed reflexes (ankle and/or knee); and clusters of tests (radiculopathy, cluster of at least 2 tests, root compression and neurological disturbances).
Reference standard test against which the new test was compared
The inclusion criteria were not defined in terms of a 'gold' standard test. The included studies used the following as 'gold' standard reference tests: operative findings, myelography, computed tomography, magnetic resonance imaging and combinations of tests.
Participants included in the review
Studies that included patients with sciatica and/or disc herniation were eligible. The included studies were conducted in secondary or tertiary care patient populations (69% in surgical and 31% in non surgical departments).
Outcomes assessed in the review
Studies that reported undefined test properties of diagnostic tests were eligible. Sensitivity, specificity, and the positive and negative predictive values appear to have been extracted (when they were either reported or calculable).
How were decisions on the relevance of primary studies made?
Three assessors read the full papers and any disagreements were resolved by consensus.