Reference values, minimum repetitions for stable measures, and test-retest reliability in the torsion and...

To determine reference values, including the appropriate number of repetitions, and test-retest reliability of the torsion and conventional cervical joint position sense (JPS) tests.

Phase 1) Cross-sectional design to determine reference values and the appropriate number of repetitions; Phase 2) repeated-measures concordance design (test-retest reliability). Sixty-eight healthy participants performed 10 repetitions of randomized rotation left and right for both cervical JPS tests using a laser projected onto a target. Thirty participants returned for the same evaluation process one week later.

The age-stratified reference values for the torsion JPS test showed greater absolute error as age increased. Stable levels of performance were obtained with 6-7 repetitions for both tests. Moderate to good reliability was found with 7 or more repetitions for left rotation [Torsion JPS test, Intraclass Correlation Coefficient (ICC; 95% CI) = 0.85 (0.68-0.93); Conventional JPS test, ICC = 0.78 (0.53-0.89)], and 6-7 or more repetitions for right rotation [Torsion JPS test, 6 repetitions, ICC = 0.79 (0.56-0.90); Conventional JPS test, 7 repetitions, ICC = 0.82 (0.61-0.91)]. Standard Error of Measurement (SEM) and Minimal Detectable Change (MDC) stabilized at 7 repetitions in both tests [Torsion JPS test (SEM ≤ 1.0°; MDC₉₀ ≤ 2.4°; MDC₉₅ ≤ 2.9°); Conventional JPS test (SEM ≤ 1.2°; MDC₉₀ ≤ 2.8°; MDC₉₅ ≤ 3.3°)].

The reference values generated for the torsion JPS test may help identify the presence of impairments cervical proprioception. At least 7 repetitions optimize stability, reliability and responsiveness in the torsion and conventional cervical JPS tests.