BACKGROUND In the past two decades, there has been a growing interest in the development of a more patient-centred approach to assessing treatment outcomes. This interest has resulted in the increasing use of patient-reported outcome measures (PROMs) in both clinical trials and usual clinical practice. OBJECTIVE To briefly discuss the paucity of efficacy and effectiveness studies in the field of mental health (exemplified by schizophrenia, depression and opioid dependence) that significantly incorporate the patient's perspective. The limited concordance between the perspectives of patients and clinicians in outcome assessment is also addressed. Finally, we propose a new PROM classification system based on the degree to which these instruments incorporate the patient's perspective. CONCLUSIONS PROMs may differ little from traditional instruments unless they truly incorporate the patient's perspective and not just the perspectives of clinicians and researchers. Efforts to develop new PROMs that provide a more patient-centred outcome assessment should use qualitative and participatory methods to capture and incorporate patient perspectives and values.