The quality of the evidence was assessed using the GRADE approach.20 The quality of the evidence starts at high when at least two trials provide results for an outcome. The quality is reduced by one level for each of the following domains not met: limitations of the study design, defined as > 25% of the participants from studies with a high risk of bias; inconsistency, defined as statistical heterogeneity
〖(I〗^2> 40%) or inconsistent findings among studies (< 75% of the participants reported findings in the same direction); indirectness, defined as generalisability of the findings; imprecision of results, defined as total number of participants < 300 for a dichotomous outcome and < 400 for continuous outcome; and ‘other’, such as publication bias, flawed design or massive dropout. Single randomised trials (n < 400) were considered to be Box 1. Inclusion criteria. Design Randomised trial Published in any language Participants Adults with a common musculoskeletal disordera Intervention Massage, defined as systematic manual manipulation of the soft tissues of the body with rhythmical pressure and stroking Outcome measures Pain Function Comparisons Massage versus no treatment (wait list control, sham, rest or usual care) Massage versus other active treatments (exercise therapy, joint manipulation, relaxation therapy) a Common musculoskeletal disorders were defined by the International Classification of Primary Care (ICPC) codes chapter L: locomotor system.46 Research 107 inconsistent and imprecise, and provided low-quality evidence, which could be further downgraded to very-low-quality evidence.