Standardized outcome measures can enhance clinical decision making in hand therapy. Processes in which evidence is used to make decisions on individual patients with respect to the patient's level of impairment and disability as well as the significance of any changes observed after interventions are consistent with an evidence-based approach. Evidence can enhance clinical decision making and provide objective criteria for goal setting and evaluation. The authors review the necessary concepts and approaches to applying evidence on outcome measures using a vignette that describes a patient with rotator cuff pathology who has provided a Disability of the Arm, Shoulder, and Hand (DASH) score during clinical assessment.