Biases in diagnostic terminology: Clinicians choose different symptom labels depending on whether the same case is framed as depression or schizophrenia.

Negative symptoms in schizophrenia show striking similarities to some depressive symptoms. Different terms are often used for these phenomenologically similar symptoms depending on the context, such as avolition (most often used in the context of schizophrenia) and lack of drive (most often used in the context of depression). To test whether clinicians assign different symptom labels to the same clinical picture based on the cued diagnosis, 98 clinical psychologists and psychiatrists were presented with two case studies that were randomly framed as characterizing an individual with either depression or schizophrenia. An interaction of the symptom label group selected by the clinicians with the framing condition confirmed our hypothesis: despite identical content, clinicians favored different clinical terms depending on the cued diagnosis (p = .025, η2partial = 0.054). This result was supported by the suspected diagnosis suggested by the clinicians; numerically, they more often confirmed than rejected the cued diagnosis. The present study is in line with earlier findings indicative of strong overlap pertaining to the phenomenology of negative symptoms in schizophrenia and depressive symptoms that suggest that clinical terminology should be streamlined. The hypothesis that core symptoms of both syndromes tap largely the same construct should be further pursued. If true, the concept of negative symptoms, currently used to describe schizophrenia alone, should be opened up for describing symptoms in other disorders. This could help to gain a deeper understanding of the transdiagnostic appearances of the negative syndrome.