The use of parametric effect sizes in single study musculoskeletal physiotherapy research: A practical primer

Many researchers often do not report effect sizes at all, and, if they do report them, often do not report the correct measure for the design that has been used in the research. With the increased level of attention being given to the reporting of effect sizes and their corresponding confidence intervals, it is important that there is field-specific literature pertaining to the calculation and reporting of these measures. This paper acts as a practical primer for the calculation and reporting of effect size measures aimed at, but not limited to, the field of musculoskeletal physiotherapy research. This primer involves a discussion on which effect sizes are appropriate for within and between-subject single study research, illustrating, through examples based on musculoskeletal research data, how these measures are calculated, interpreted, and reported.