Osteopaths, and other practitioners of manual medicine employ a variety of procedures in assessing a patient in order to determine a diagnosis and subsequent treatment plan. The physical assessment generally includes visual observation, static palpation and motion testing. Despite the reliance upon assessments of this type, many of the assessment procedures used remain questionable. The aim of this study was to determine the inter- and intra-examiner reliability of a commonly used three part positional diagnostic screen for the lumbar spine. Ten examiners performed the three part positional diagnostic screen on ten asymptomatic female subjects. Intraexaminer reliability ranged from less than chance to slight agreement ( K = −0.14 − 0.16) with a mean Kappa value of 0.04. Inter-examiner reliability showed slight agreement with a Kappa coefficient of 0.04. There was no real agreement either within or between examiners for the three-part static palpation diagnostic procedure for the lumbar spine. This might indicate that this particular procedure ought to be used with caution by new graduates, despite the fact that it would appear to be a well-known procedure, as documented in at least five widely utilised osteopathic texts. These results suggest that the reliability of the three part positional diagnostic screen for the lumbar spine remains questionable.