When a clinician asks How do I test for schizophrenia? they follow a structured, rule-based process. Below are specific, evidence-based steps.
- Structured diagnostic interview (first step).
- Use a semi-structured tool (SCID-5) to map symptoms to DSM-5 criteria.
- Record onset, duration, and impact on work or relationships.
- Symptom rating and severity scales.
- Administer PANSS or BPRS to quantify positive, negative, and general symptoms.
- Repeat ratings over weeks to detect change.
- Targeted medical exclusion tests.
Order tests to exclude medical or substance causes:- Urine toxicology (amphetamines, cannabis, PCP, cocaine).
- CBC, electrolytes, liver and renal panel.
- Thyroid function (TSH), vitamin B12, folate.
- Syphilis serology and HIV when risk factors exist.
- ECG if antipsychotic treatment is being considered.
These reduce false positives and guide safe treatment.
- Neurophysiology and imaging — when indicated.
- MRI brain is recommended in first-episode, atypical, or focal-neurology presentations.
- EEG is indicated for seizure-like events or fluctuating consciousness.
Use imaging only to rule out structural or neurologic mimics.
- Cognitive and functional mapping.
- Perform brief cognitive batteries (working memory, processing speed).
- Document daily functioning and social decline. This informs prognosis and rehabilitation.
- Apply DSM-5 timing and longitudinal criteria.
- Confirm symptom persistence and active-phase duration per DSM-5 before labeling schizophrenia.
Testing is diagnostic and prognostic. Use the results to build a treatment plan that pairs antipsychotic management with psychosocial rehabilitation. If you specifically ask How do I test for schizophrenia? expect a multi-step, documented process that combines interview, scales, targeted labs, selective imaging, and longitudinal follow-up.