Integrating clinical staging and phenomenological psychopathology to add depth, nuance, and utility to clinical phenotyping: a heuristic challenge.

Psychiatry has witnessed a new wave of approaches to clinical phenotyping and the study of psychopathology, including the US National Institute of Mental Health's Research Domain Criteria, clinical staging, network approaches, the Hierarchical Taxonomy of Psychopathology, the general psychopathology factor, and a revival of interest in phenomenological psychopathology. The question naturally emerges about what the relationship between these new approaches is. Are they mutually exclusive and competing approaches, or can they be integrated in some way and be used to enrich each other? In this Personal View, we propose a possible integration between clinical staging and phenomenological psychopathology. Domains identified in phenomenological psychopathology (eg, selfhood, embodiment, and affectivity) can be overlaid on clinical stages to enrich and deepen the phenotypes captured in clinical staging (creating high-resolution clinical phenotypes). This approach might be useful both ideographically and nomothetically, to complement diagnosis, enrich clinical formulation, inform treatment of individual patients, and help to guide aetiology research, prediction of clinical trajectory and treatment. Overlaying phenomenological domains on clinical stages might require reformulating these domains in dimensional rather than categorial terms. This integrative project requires assessment tools (some of which are already available) that are sufficiently sensitive and thorough to pick up on the range of relevant psychopathology. The proposed approach offers opportunities for mutual enrichment: clinical staging might be enriched by introducing greater depth to phenotypes; phenomenological psychopathology might be enriched by introducing stages of severity and disorder progression to phenomenological analysis.