The diagnosis of cervical spondylitis (CS) is based on three factors: clinical, neuroradiological and neurophysiological data. However, in spite of being universally used, the validity of each of these diagnostic instruments has still to be clarified. The objective of our study was to make a critical analysis of the evidence currently available with regard to the diagnosis of CS.Review of the literature from 1967 to March 2001, quoted by MEDLINE, regarding the diagnosis of CS. The articles obtained were classified into four groups: Metanalysis or systematic reviews, controlled studies with a surgical pattern of reference, controlled studies with another pattern of reference or not controlled and cases or series of cases. We made a critical analysis of each of the articles obtained.There is no clinical test or investigation which may be considered to be a definite diagnostic marker, so the degree of diagnostic certainty depends on the combination of investigations and their agreement with the clinical history and examination. The data from clinical examination may be considered to be extremely useful in the diagnosis of CS. Neuroimaging investigations are characterized by their high sensitivity and low specificity, so these methods should be used early in the process of making a diagnosis of CS. The myelo CAT scan is better than MR in the diagnosis of spondylitic cervical radiculopathy (SCR). The new MR techniques have considerably improved the possibilities of diagnosis of SCR, but there is no evidence that they are currently as good as the myelo CAT scan. MR is the method of choice for assessment of intrinsic spinal disorders, although there is some evidence that the degree of cervical stenosis may be underestimated when MR is used. The neurophysiological diagnosis (EMG) in SCR is of high specificity since it gives only a small proportion of false positive results. Somatosensory evoked potentials (PESS) from the tibialis posterior is a highly sensitive test for the diagnosis of spondylitic cervical myelopathy (SCM). The combination of PESS and motor evoked potentials may be useful for the detection of patients with SCM at presymptomatic stages and for differentiation between spinal and root involvement. It is essential to carry out studies to evaluate the available diagnostic tests based on specificity. These studies should be the first step in making it possible to design studies to determine the natural history of CS and the therapeutic effectiveness of the techniques currently in use.