Inter-examiner reliability in assessing passive intervertebral motion of the cervical spine.

Passive intervertebral motion of the cervical spine was assessed independently by two physical therapists. The therapists had equal backgrounds concerning education and clinical experience. Sixty-one patients seeking care for cervical problems at a private clinic were included in the study where three segments of the cervical spine and the mobility of the first rib were graded as stiff or not stiff. Data were analysed by percentage agreement and kappa coefficient which indicates inter-examiner reliability greater than expected by chance. Results demonstrated inter-examiner reliability of between 70 and 87% and kappa coefficients ranging between 0.28 and 0.43 considered to be only 'fair to moderate'.