Kubas, C, Chen, Y-W, Echeverri, S, McCann, S, Denhoed, M, Walker, C, Kennedy, C, and Reid, WD. Reliability and validity of cervical range of motion and muscle strength testing. J Strength Cond Res 31(4): 1087-1096, 2017-Cervical range of motion (ROM) and strength are fundamental measures to assess treatment effectiveness. The JTECH wireless devices provide versatile means of quantifying these measurements. The purpose of this study was to determine intrarater and interrater reliabilities and concurrent validity of the JTECH wireless dual inclinometer and handheld dynamometer. This study included 20 healthy subjects (mean age = 28.7 ± 7.8 years). The directions of ROM movement measured were cervical flexion, extension, lateral flexion, and rotation. Isometric strength was measured for flexion, extension, and lateral flexion. Two testers measured cervical ROM and isometric strength for each subject using the JTECH devices during 2 or 3 sessions to determine reliability. The same ROM and muscle strength movements were measured using the CROM3 and MicroFET2, respectively, to assess concurrent validity. Reliability and validity were analyzed using intraclass correlation coefficient (ICC), along with SEM and minimal detectable change. The results of this study showed that the intrarater reliability of the JTECH inclinometer and dynamometer was moderate to excellent (ICCs (3,1) = 0.53-0.90 and 0.74-0.91, respectively). The interrater reliability of the JTECH inclinometer was moderate to excellent (ICCs (2,3) = 0.69-0.89), whereas the JTECH dynamometer showed excellent interrater reliability (ICCs (2,3) = 0.84-0.88). The JTECH inclinometer and dynamometer showed moderate to excellent concurrent validity (ICCs (3,2) = 0.65-0.91 and 0.91-0.96, respectively). With the ease of use, portability, and ability to record multiple measurements without stopping, these devices can be applied to clinical and research settings.