Physical Therapy Evaluation Tool (PEAT) 4 Practice Exam

Effect size in PT outcome studies measures how big the treatment effect is, independent of how many participants were studied. A large effect size means the observed change or difference due to the intervention is substantial, indicating a meaningful impact on patient function or pain. This emphasis on magnitude helps clinicians judge practical importance beyond just statistical significance. Remember that p-values and sample size influence whether a result is statistically significant, but do not by themselves tell you how large the effect is. So a large effect size best describes a substantial treatment effect, whereas a large sample size alone does not imply a large effect, and a p<0.05 result does not guarantee the effect is large. Clinical relevance often aligns with a large effect size, though it isn’t guaranteed in every case.