Interrater and Intrarater Reliability of the Congenital Muscular Torticollis Severity Classification System.

PURPOSE: To establish inter- and intrarater reliability for determining severity grades of the congenital muscular torticollis severity classification system (CMT-SCS).

METHODS: A prospective reliability study with 145 physical therapists recorded severity ratings on 24 randomly-ordered patient cases including age of infant, cervical range of motion, and presence or absence of sternocleidomastoid mass. To compute intrarater reliability, cases were randomly reordered and graded by 82 of the original raters.

RESULTS: For the CMT-SCS, overall reliability was good with an interrater reliability intraclass correlation coefficient (ICC) (2,1) of 0.83 (95% confidence interval [CI], 0.74-0.91) and an intrarater reliability ICC (3,1) of 0.81 (95% CI, 0.66-0.91).

CONCLUSIONS: The CMT-SCS has good reliability for infants up to 12 months of age. Physical therapists can use the scale for initial assessment of infants suspected to have CMT. The CMT-SCS should be standard documentation for infants with CMT.