The ICD-11 requires a minimum period of symptoms of ≥1 month. The six symptom domains captured in ICD-11 are positive, negative, depressive mood, manic mood, psychomotor, cognitive.4 Negative symptoms include diminished emotional expression, avolition, alogia or paucity of speech, asociality, and anhedonia.4 The 4‑point scale (not present, mild, moderate, and severe), appears in the main body of guidelines.4
DSM-5 requires that continuous signs of disturbance persist for at ≥6 months. The three positive‑symptom domains captured in DSM-5 are hallucinations, delusions, disorganized speech, which encompass the positive symptom dimension, plus negative, cognition, psychomotor, depression, mania domains.4 Manifestation of ≥2 positive symptoms must be present for a diagnosis of schizophrenia.10 Negative symptoms are limited to diminished emotional expression and avolition.4 The 5‑point scale (not present, severe), is captured in the appendix.4
Abbreviations: DSM-5=Diagnostic and Statistical Manual of Mental Disorders, fifth edition, text revision; ICD-11=International Classification of Diseases, eleventh revision
References:
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