PROs are status reports on a patient’s health condition or health behavior that comes directly from the patient, without interpretation of the patient’s response by a clinician or anyone else. This definition reflects the key domains of health-related quality of life (including functional status), symptoms and symptom burden (e.g., pain, fatigue), and health behaviors (e.g., smoking, diet, exercise). (Adapted from the Food and Drug Administration Guidance for Industry PRO Measures: Use in Medical Product Development to Support Labeling Claims)