The Wong-Baker Faces Pain Rating Scale (styled Wong-Baker FACES Pain Rating Scale) is a pain scale that was developed by Donna Wong and Connie Baker. The scale shows a series of faces ranging from a happy face at 0, "No hurt" to a crying face at 10 "Hurts worst". The patient must choose the face that best describes how they are feeling.
References
Wong-Baker Faces Pain Rating Scale Wikipedia(Text) CC BY-SA