Intraexaminer reliability of hand-held dynamometry in the upper extremity: a systematic review

To summarize and appraise the literature on the intraexaminer reliability of hand-held dynamometry (HHD) in the upper extremity. MEDLINE, CINAHL, and EMBASE were searched for relevant studies published up to December 2011. In addition, experts were contacted, and journals and reference lists were hand searched. To be included in the review, articles needed to (1) use a repeated-measures, within-examiner(s) design; (2) include symptomatic or asymptomatic individuals, or both; (3) use HHD to measure muscle strength in any of the joints of the shoulder, elbow, or wrist with the "make" or the "break" technique; (4) report measurements in kilogram, pound, or torque; (5) use a device that is placed between the examiner's hand and the subject's body; and (6) present estimates of intraexaminer reliability. Quality assessment and data extraction were performed by 2 reviewers independently. Fifty-four studies were included, of which 26 (48%) demonstrated acceptable intraexaminer reliability. Seven high-quality studies showed acceptable reliability for flexion and extension of the elbow in healthy subjects. Conflicting results were found for shoulder external rotation and abduction. Reliability for all other movements was unacceptable. Higher estimates were reached for within-sessions reliability and if means of trials were used. Intraexaminer reliability of HHD in upper extremity muscle strength was acceptable only for elbow measurements in healthy subjects. We provide specific recommendations for future research. Physical therapists should not rely on HHD measurements for evaluation of treatment effects in patients with upper extremity disorders