Intra- and inter-rater reliability of neutral head position and target head position tests in patients with and without neck pain

BACKGROUND Cervical proprioception is a common term used in neck rehabilitation, and it is examined using neutral head position (NHP) and target head position (THP) tests. OBJECTIVE To investigate intra- and inter-rater reliability of the NHP and THP tests in patients with neck pain and in healthy controls. METHODS The intra-rater (between-day) and inter-rater (within-day) reliability of the NHP and THP tests were assessed in 36 patients with neck pain and 33 healthy subjects. NHP testing was evaluated in cervical extension, while THP testing was evaluated in six directions of cervical motion: cervical flexion, extension, side bending right, side bending left, rotation right, and rotation left. RESULTS The intra-rater reliability for the NHP tests had intraclass correlation coefficient (ICC) values of 0.74-0.78 and a standard error of measurement (SEM) of 1.78-1.88; the THP tests had ICC values of 0.70-0.83 and SEM of 1.45-2.45. Likewise, inter-rater reliability for NHP had ICC values of 0.74-0.79 and SEM of 1.79-1.87. For the THP test, the inter-rater reliability had ICC values of 0.62-0.84 and SEM of 1.50-2.23. CONCLUSION Intra- and inter-rater reliability ranged from good to very good agreement both for NHP and for THP tests of cervical proprioception.