Observerreported

Observer-reported outcomes, often abbreviated as ObsROs, are assessments of a patient’s condition provided by someone other than the patient, such as a parent, caregiver, or trained clinician. They are used when the patient cannot reliably report symptoms or experiences themselves, for example in young children, individuals with cognitive impairment, or nonverbal patients. ObsROs focus on observable signs, behaviors, and events rather than internal states that the patient alone would need to report.

Observers may document symptoms, functioning, daily activities, or health events based on their observations over a specified period. In pediatric research, for instance, ObsROs are commonly employed to capture aspects like sleep disruption, pain-related behaviors, fever patterns, or energy levels. Distinguishing ObsROs from patient-reported outcomes (PROs) and clinician-reported outcomes (ClinROs helps clarify the perspective and potential biases involved in data collection.

Development of ObsRO measures involves constructing a conceptual framework, creating items that observers can reliably rate, and testing for reliability and validity. Psychometric properties such as inter-rater reliability, test-retest reliability, content validity, construct validity, and responsiveness to change are evaluated. Cross-cultural adaptation and training for observers may be necessary to ensure consistency.

Regulatory contexts recognize ObsROs as relevant evidence in trials where patient self-report is not feasible. Their use requires rigorous demonstration of reliability and relevance to the patient’s health status and treatment outcomes. Potential limitations include observer bias, reporting bias, and variations in observer interpretation.