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Abstract
Background and Purpose.  The deep neck flexor muscles (DNFs) stabilize the cervical spine and cervicogenic pain appears to adversely affect their endurance capacity. They are inaccessible to direct palpation, thereby making assessment difficult. However, the cranio-cervical flexion test (CCFT) provides an indirect method of assessing the endurance capacity of the DNFs. The purpose of the present study was to evaluate the intratester reliability of the CCFT in asymptomatic subjects.

Method.  The clinical protocol of the CCFT was measured on two occasions with 7 days between measurements. Prior to testing, participants were trained and compensation strategies were corrected. Nineteen asymptomatic participants (mean age 24.9 years; range 22-36) were recruited.

Results.  The test had excellent intratester reliability (intraclass correlation coefficient = 0.983; standard error of the mean = 8.94; smallest real difference = 24.7). A Bland and Altman's limits of agreement analysis confirmed the high reliability of the test.

Conclusion.  The CCFT results demonstrated excellent intra-tester reliability in asymptomatic subjects, thus contributing to the normative data regarding the test.