Interexaminer agreement for muscle palpation procedures: the efficacy of a calibration program

The purpose of this study is to assess the muscle palpation interexaminer agreement after a calibration program and to determine differences between time, groups of muscles, or side examined. A sample of 32 individuals, matched for sex, was divided into two groups: symptomatic (16 patients presenting with myogenic TMD) and asymptomatic (16 subjects with no TMD symptoms). Palpation procedures were performed three different times by four calibrated examiners, in masticatory and cervical muscles. The presence or severity of tenderness was judged by an ordinal scale (from "0" to "3"). Kendall's concordance test measured agreement between examiners. The sternocleidomastoid muscle showed the highest agreement (0.84), while the worst result was detected for the origin of the masseter (0.56). Levels of agreement for all muscles were considered fair and excellent, regardless of the time of examination or the side analyzed.