Inter-clinician and intra-clinician reliability of force application during joint mobilization: a systematic review

Joint mobilizations are commonly used by clinicians to decrease pain and restore joint arthrokinematics following musculoskeletal injury. The force applied during a joint mobilization treatment is subjective to the individual clinician but may have an effect on patient outcomes. The purpose of this systematic review was to critically appraise and synthesize the studies which examined the reliability of clinicians' force application during joint mobilization. A systematic search of PubMed and EBSCO Host databases from inception to March 1, 2013 was conducted to identify studies assessing the reliability of force application during joint mobilizations. Two reviewers utilized the Quality Appraisal of Reliability Studies (QAREL) assessment tool to determine the quality of included studies. The relative reliability of the included studies was examined through intraclass correlation coefficients (ICC) to synthesize study findings. All results were collated qualitatively with a level of evidence approach. A total of seven studies met the eligibility and were included. Five studies were included that assessed inter-clinician reliability, and six studies were included that assessed intra-clinician reliability. The overall level of evidence for inter-clinician reliability was strong for poor-to-moderate reliability (ICC = -0.04 to 0.70). The overall level of evidence for intra-clinician reliability was strong for good reliability (ICC = 0.75-0.99). This systematic review indicates there is variability in force application between clinicians but individual clinicians apply forces consistently. The results of this systematic review suggest innovative instructional methods are needed to improve consistency and validate the forces applied during of joint mobilization treatments. This is particularly evident for improving the consistency of force application across clinicians.