Patient-proxy agreement on health-related quality of life assessment in cancer patients.

Abstract

Purpose of review: The aim of this study was to examine the role of proxy-reported outcomes in oncology, particularly in neuro-oncology, where cognitive impairment and disease progression often limit patient' ability to self-report. With increasing emphasis on patient-centered care and regulatory requirements for clinical outcome assessments (COAs), it is essential to understand when and how proxy reports can substitute or complement patient-reported outcomes (PROs), particularly in the assessment of health-related quality of life (HRQoL).

Recent findings: Use of proxy-reported outcomes in cancer clinical trials is common. Proxy reports can help reduce missing data and selection bias by replacing PROs in patients with a poor health condition. However, studies consistently show poor to moderate agreement between patient and proxy reports of HRQoL outcomes, with the lowest congruence in less observable areas such as emotional functioning. Most proxy reports rely on PRO instruments not validated for proxy use, and heterogeneity in statistical methods, proxy selection, and proxy instruction further complicates interpretation.

Summary: While proxy-reported outcomes should not replace PROs when patients can self-report, they offer valuable insights when self-report is not feasible. When standardized methods are followed, such as using validated instruments and clearly defining the reporting perspective, proxy reports can serve as a useful alternative in clinical trials and clinical practice.