This Visual Analog Scale allows reliable pain evaluation.
Its simple, its free and with no ads ! Now your VAS is always available, right in your pocket !
Accuracy, Validity, and Reliability of an Electronic Visual Analog Scale for Pain on a Touch Screen device has been scientifically evaluated : https://www.ncbi.nlm.nih.gov/pubmed/26769149
Herve Kasparian D.O. and Ghislaine Signoret D.O., two osteopaths in Tonneins (France), are happy to provide this tool to you.