Relationships between the Verbal Visual Analog Scale (VB-VAS) and the Gracely Box SL scale for volunteers' perception of pain associated with injections using different needle types. The solid grey line is the fitted line and the dashed grey lines are simultaneous 95% predictions boundaries for the whole line. The green line represents the line of perfect agreement and the estimated equation that characterizes the relationship is: VB-VAS = 8.38 + 3.12*Gracely. TPE, Thermo Plastic Elastomer.
Jaber et al. BMC Neurology 2008 8:38 doi:10.1186/1471-2377-8-38