Interexaminer reliability and concurrent validity of two instruments for the measurement of cervical ranges of motion.

The reliability of measurement of cervical ranges of motion (ROM) has rarely been studied. The current study evaluated the interexaminer reliability and concurrent validity of two instruments (rangiometer and goniometer) for measuring cervical ranges of motion. Twenty-four consenting subjects were assigned to random orders of examiners, instruments and planes of motion. Thirteen measurements of cervical motion and neutral positions were evaluated by two examiners using each instrument. Interexaminer reliability coefficients were generally greater than interinstrument coefficients, and both were higher than a combination of interexaminer/interinstrument predictions. The r values for rangiometric objectivity were higher than those of the goniometer in 9 of 10 cervical ranges of motion. The rangiometer is a moderately reliable instrument for measuring cervical ranges of motion.