Assessment of a clinical outcome can be made through report by a clinician, a patient, a non-clinician observer or through a performance-based assessment. There are four types: 

1. Patient-reported outcome (PRO), 
2. Clinician-reported outcome (ClinRO) measures,
3. Observer-reported outcome (ObsRO), and 
4. Performance outcome (PerfO).

FDA: Patient-Focused Drug Development Glossary | BEST Glossary