Linear Analogue Self-Assessment and Procrustean Measurement: A Critical Review of Visual Analogue Scaling in Pain Assessment

Visual analogue scales (VASs) are one of the most widely used self-report measures of clinical pain. This article reviews the empirical literature on linear analogue self-assessment (LASA) and critically examines the features that appear to have made it such an attractive measurement option in pain assessment. It is concluded that analogue scaling does not withstand critical scrutiny as a primary measure of either pain intensity or pain affect and that, in most circumstances, the overall clinical utility of VASs is inferior to that of more structured pain indices.