Examination Procedures.— At the beginning of the study, an independent assessor, who was not involved with the treatment of the patients, underwent a 1-hour training session in which he practiced the examination procedures to ensure that they were performed in a standardized fashion in all subjects. The following physical examinations were performed by this assessor on all patients before their inclusion in the therapy program: cervical range of motion, pressure pain thresholds, total tenderness score, and examination of muscle TrPs.
Cervical range of motion was assessed with a goniometer CROM (Performance Attainment Associates), which has been shown to have good intra-tester (ICC 0.7-0.9) and inter-tester (ICC 0.8-0.87) reliability. 36 The motion for each neck movement in a single movement direction was measured in a standard fashion as follows: flexion, extension, right and left lateral flexion, right and left rotation. Three measurements were performed for each direction of movement and the mean of the 3 trials was employed in the analysis.