Reliability of still photography measuring habitual head deviation from midline in infants with congenital muscular torticollis

Abstract

Purpose: To establish intrarater and interrater reliability of still photography for measuring habitual head deviation from midline in infants with congenital muscular torticollis (CMT).

Methods: Two investigators took still photographs of 30 infants with CMT in a supine position and measured head deviation angles with a protractor. Data analysis included paired t tests, Pearson r, and intraclass correlation coefficients (ICC) with 95% confidence intervals.

Results: Pearson r varied from 0.80 to 0.85 for the same rater and from 0.72 to 0.99 for 2 different raters. The ICC (3,1) varied from 0.79 to 0.84, and ICC (2,1) varied from 0.72 to 0.99. Participants with smaller head-tilt angles showed greater variability in head position.

Conclusions: Still photography is a reliable method for measuring habitual head deviation from midline in infants with CMT. Several modifications to the measurement procedure have been suggested.