Psychiatry Calculators

Patient Health Questionnaire-9 for screening and monitoring depression severity.

Two-item ultra-brief screening tool for depression. Score ≥3 warrants full PHQ-9.

Generalised Anxiety Disorder 7-item scale for screening and severity assessment.

WHO 10-item questionnaire to identify hazardous/harmful alcohol use and alcohol dependence.

Abbreviated 3-item version of AUDIT. Score ≥3 (women) or ≥4 (men) is positive.

Four-question screening tool for alcohol misuse. Score ≥2 is clinically significant.

Clinical Institute Withdrawal Assessment for Alcohol — Revised. Guides benzodiazepine dosing in alcohol withdrawal.

Clinical Opiate Withdrawal Scale. Guides buprenorphine induction timing and severity monitoring.

10-item clinician-rated scale for measuring severity of depression episodes. Commonly used in clinical trials.

Self-administered 8-item questionnaire measuring daytime somnolence. Used to screen for sleep disorders including OSA.

15-item yes/no scale validated for depression screening in the elderly.

10-item yes/no questionnaire assessing drug misuse (excluding alcohol and tobacco) in the past 12 months.

10-item mnemonic scale for assessing suicide risk. Each positive factor scores 1 point.

Clinician-rated 11-item scale measuring severity of manic episodes. Widely used in bipolar disorder trials.

Standardised tool for assessing suicidal ideation and behaviour. Used in emergency, inpatient, and outpatient settings. Recommended by FDA for clinical trials and widely adopted globally.

Predicts risk of aberrant drug-related behaviour in patients prescribed opioids for chronic pain. Scored separately for male and female patients.

Clinician-administered 17-item scale measuring depression severity. Standard outcome measure in antidepressant trials and clinical practice.

Self-report screening tool for bipolar spectrum disorders. Positive screen requires ≥7 of 13 symptoms, symptom clustering, and moderate/serious functional impairment.

20-item self-report measure of DSM-5 PTSD symptom severity. Score 0–80. Provisional PTSD diagnosis threshold: score ≥33.

Abbreviated PANSS assessing positive, negative, and general psychopathology domains in schizophrenia and related disorders. Full PANSS is 30-item; this abbreviated version covers key domains.

25-item structured interview for detecting lifetime alcohol use disorder. Score ≥5 indicates possible alcohol problem.

CRAFFT screening tool for alcohol and substance misuse in adolescents (12–21 years). CRAFFT = Car, Relax, Alone, Forget, Friends, Trouble.

15-item self-report screening tool for depression in older adults (>65 years). Avoids somatic items that confound depression screening in the elderly. Short form of original 30-item GDS.

Brief validated tool for assessing alcohol withdrawal severity in clinical settings. Assesses 8 domains. Score ≥5 suggests significant withdrawal requiring pharmacological management.

Validated 5-item scale for monitoring alcohol withdrawal severity. Developed at Glasgow Royal Infirmary. Simpler than CIWA-Ar and validated in UK acute settings. Score ≥2 = consider benzodiazepines.

10-item tool to predict risk of complicated alcohol withdrawal (seizures, delirium tremens) before symptoms develop. Score ≥4 = high risk requiring prophylactic benzodiazepines.

16-item self-rated scale measuring severity of opiate withdrawal symptoms. Score 0–64. Complements objective COWS scale. Used to monitor withdrawal in opioid detoxification.

17-item instrument for monitoring patients in addiction treatment. Assesses substance use, protective factors, and risk factors for relapse. Designed for routine use at each treatment visit.

14-item clinician-administered scale measuring anxiety severity. Each item rated 0–4. Total score 0–56. Widely used in clinical trials and clinical practice for anxiety disorders.

10-item self-report depression scale derived from ICD-10 and DSM-IV criteria. Can be used as a severity measure (score 0–50) or for diagnosis of depression. Validated in primary care and general practice.

16-item (QIDS-C clinician-rated; QIDS-SR self-report) measure of depression severity based on 9 DSM-IV symptom domains. Score 0–27. Used in clinical trials and STAR*D study.

5-item screen for PTSD in primary care settings. A positive screen (≥3) warrants further evaluation. Validated against structured clinical interview (SCID). Requires a traumatic event as a precondition.

10-item self-report scale for screening perinatal depression in pregnancy and up to 1 year postpartum. Score ≥13 = probable depression. Score ≥10 = risk of depression. Item 10 (suicidal ideation) always reviewed regardless of total score.

Clinician-rated 12-item scale for assessing tardive dyskinesia and other abnormal involuntary movements in patients on antipsychotic medications. Items 1–7 are scored 0–4; items 8–12 are additional assessments.

18-item clinician-administered scale assessing psychiatric symptoms in patients with major mental illness, particularly schizophrenia. Each item 1–7. Total 18–126. Widely used in clinical trials and acute settings.

30-point cognitive screening instrument for mild cognitive impairment (MCI) and dementia. Assesses visuospatial, naming, memory, attention, language, abstraction, and orientation. Score <26 = cognitive impairment. +1 point if ≤12 years education.

7-point self-report scale measuring subjective level of sleepiness at a given moment. Developed at Stanford. Used in sleep research and clinical assessment. Score 1 = feeling active/alert; score 7 = fighting sleep.

18-item self-report screening tool for adult ADHD developed with WHO. Part A (items 1–6) is the validated screener — a positive screen requires ≥4 items shaded in the dark zone. Full 18-item scale assesses full symptom picture.

15-item somatic symptom severity scale derived from the full PHQ. Score 0–30. Assesses frequency of physical complaints with no medical explanation. Score ≥10 = high somatic symptom severity.

6-item screening tool for problematic substance use in adolescents (12–21 years). CRAFFT is an acronym: Car, Relax, Alone, Forget, Friends, Trouble. Score ≥2 = positive screen for problem use.

5-item screening questionnaire for anorexia nervosa and bulimia nervosa. Validated in primary care. Score ≥2 = likely eating disorder. SCOFF = Sick, Control, One stone, Fat, Food.

Revised version of the Opioid Risk Tool specifically predicting opioid use disorder (OUD) risk in patients prescribed opioids for chronic pain. 5 items, score 0–26. Score ≥8 = high risk.

13-item brief version of the MAST for alcohol use disorder screening. Score ≥3 = probable alcoholism. Score 1–2 = possible; score 0 = unlikely. Validated in multiple settings.

7-point single-item scale for rapidly assessing sedation and agitation in clinical settings. Used to guide pharmacological management of acute agitation. Score 1 = difficult to arouse; score 4 = calm; score 7 = violently agitated.

10-item version of the SMAST adapted for older adults (≥65 years). Addresses age-specific alcohol use issues (drinking to cope, loneliness, pain). Score ≥2 = probable alcohol use problem.

DSM-5 diagnostic criteria checklist for Major Depressive Disorder (MDD). Requires ≥5 symptoms for ≥2 weeks, with at least one being depressed mood or anhedonia, causing significant distress or functional impairment.

DSM-5 diagnostic criteria checklist for Bipolar I (manic episode required) and Bipolar II (hypomanic + depressive episode required) disorders. Distinguishing features of mania vs hypomania are duration and impairment.

Screens for suicide risk using 10 clinical factors. Mnemonic: Sex, Age, Depression, Previous attempts, Ethanol/drug use, Rational thinking loss, Social support lacking, Organised plan, No spouse/partner, Sickness.

Guides admission to Psychiatric Intensive Care Unit (PICU) based on risk level and behavioural criteria per NAPICU standards.

10-item clinician-rated severity scale for OCD (Goodman 1989). 5 obsession items + 5 compulsion items, each 0–4. Total 0–40.

9-item clinician-rated scale designed to disentangle depressive symptoms from negative or extrapyramidal symptoms in schizophrenia (Addington 1993). Each item 0–3. Total 0–27. Cut-off ≥6 for clinically significant depression.

22-item self-report of subjective trauma response in past 7 days (Weiss 1997). Three subscales: intrusion, avoidance, hyperarousal. Each 0–4. Total 0–88.

WHO 6-item screener (Part A) for adult ADHD (Kessler 2005). Each item rated 0–4 (never to very often). Items 1–3 score 2+ and items 4–6 score 3+ are clinically significant ('darkened-box scoring'). This calc returns simple sum 0–24 — ≥4 darkened-box items strongly suggests ADHD.

47-item parent rating scale for ADHD in children 6–12 yr (Wolraich 2003). Includes 9 inattention + 9 hyperactivity items (DSM-5 Criteria A) plus oppositional, conduct, anxiety/depression screens, and 8 performance items. Picks the diagnostic category band.

Self-report disability scale across work/school, social and family/home domains (Sheehan 1996). Each domain 0–10 visual analogue. Total 0–30.