MEQ: BPS and 4P formulation for first-episode psychosis with cannabis · Psych MEQs / SAQs

Prompt

You are the psychiatry registrar in an early intervention clinic. A 19-year-old university student is referred with 6 weeks of persecutory delusions, auditory hallucinations commenting on his actions, marked social withdrawal, and declining self-care. He has smoked high-potency cannabis daily for 8 months, sleeps 3–4 hours during exam week, and has a mother treated for schizophrenia. He lives with parents who argue loudly about 'whether he is lazy or sick'. His older sister is supportive and brings him to appointments. He is unsure whether spirits or 'the university system' are targeting him. (i) Define psychiatric formulation and distinguish it from diagnosis (3). (ii) Construct a biopsychosocial × 4P (predisposing/precipitating/perpetuating/protective) formulation for this young man (8). (iii) Outline a management plan that maps explicitly onto your formulation, including risk and cultural/illness-meaning elements (6). (iv) Name two evidence anchors relevant to formulation or cultural assessment (3). (20 marks)

Model answer

Reveal model answer

(i) Definition and distinction (3). Psychiatric case formulation is a hypothesis-driven, individualised explanatory account of why this person has these problems now, integrating multi-domain data to guide intervention and communication. Diagnosis classifies a syndrome for communication, epidemiology, and evidence application. Diagnosis is necessary but not sufficient for personalised care; formulation bridges generic evidence and the individual without replacing risk or capacity assessment.[1][2]

(ii) BPS × 4P formulation (8).

[1][2]

Presenting problem. First-episode psychosis (positive symptoms, functional collapse) with heavy cannabis use and family conflict; differential remains open to substance-induced and other organic contributions pending work-up.

[1][2]

Predisposing. Biological: first-degree family history of schizophrenia (genetic vulnerability). Psychological: possible pre-morbid social vulnerability (implied by rapid isolation under stress). Social: developmental context to be expanded; structural student stress.

[1][2]

Precipitating. Daily high-potency cannabis; severe sleep restriction in exam week; academic stress as tip-over context.

[1][2]

Perpetuating. Ongoing cannabis; sleep debt; untreated psychosis; social withdrawal; parental high expressed emotion / conflicting illness explanations that may increase stress and reduce consistent support.

[1][2]

Protective. Engaged sister; still attending (brought to clinic); university role as potential future scaffold; absence of described forensic violence history in stem (still assess risk fully).

[1][2]

Mechanisms (brief). Diathesis (family loading) + cannabis/sleep stress lowered psychosis threshold; positive symptoms and paranoia drive withdrawal; withdrawal and family conflict maintain arousal and reduce reality-testing opportunities; competing explanatory models (spirits vs system) affect help-seeking and alliance.[1][2][3]

(iii) Mapped plan (6).

[1][2]

Biological: medical/organic screen appropriate to FEP; discuss antipsychotic trial targeting positive symptoms and sleep restoration; cannabis psychoeducation and harm-reduction/cessation support; sleep interventions.
Psychological: psychoeducation about psychosis; collaborative formulation in plain language; CBT for psychosis elements when engagement allows; motivational work for cannabis.
Social/family: family psychoeducation to lower EE and align a shared illness model; involve sister as support; education/university liaison when stable; practical supports.
Cultural/meaning: explore illness explanations (spirits/system) with curiosity (CFI-style); do not ridicule; negotiate a shared care plan that respects meaning while offering medical model as additional frame.
Risk: full suicide/violence/vulnerability assessment; safety plan; intensity of follow-up matched to risk and supports; least-restrictive setting that is safe.
Review: rewrite formulation after abstinence attempt, treatment response, and collateral.[1][4][5]

(iv) Evidence anchors (3). Examples: Engel on biopsychosocial levels; Macneil et al. on formulation beyond diagnosis; Owen on what formulation is; Lewis-Fernández CFI field trial / OCF operationalisation for cultural assessment.[1][2][3][4]

Common errors

Restating “schizophrenia” as the whole formulation; omitting protective factors; blaming parents without specifying EE/conflict mechanisms; ignoring cannabis/sleep as multi-role factors; no plan map; mocking spiritual explanatory models; inventing mental health act section numbers; delaying organic work-up because the story “sounds functional.”[1][2][5]

References

[1]Macneil CA, Hasty MK, Conus P, et al. Is diagnosis enough to guide interventions in mental health? Using case formulation in clinical practice BMC Med, 2012.PMID 23016556
[2]Owen G What is formulation in psychiatry? Psychol Med, 2023.PMID 36878884
[3]Engel GL The need for a new medical model: a challenge for biomedicine Science, 1977.PMID 847460
[4]Lewis-Fernández R, Aggarwal NK, Lam PC, et al. Feasibility, acceptability and clinical utility of the Cultural Formulation Interview: mixed-methods results from the DSM-5 international field trial Br J Psychiatry, 2017.PMID 28104738
[5]Lewis-Fernández R, Aggarwal NK, Bäärnhielm S, et al. Culture and psychiatric evaluation: operationalizing cultural formulation for DSM-5 Psychiatry, 2014.PMID 24865197

Model answer

Reveal model answer

(ii) BPS × 4P formulation (8).

[1][2]

Precipitating. Daily high-potency cannabis; severe sleep restriction in exam week; academic stress as tip-over context.

[1][2]

Protective. Engaged sister; still attending (brought to clinic); university role as potential future scaffold; absence of described forensic violence history in stem (still assess risk fully).

[1][2]

(iii) Mapped plan (6).

[1][2]

Biological: medical/organic screen appropriate to FEP; discuss antipsychotic trial targeting positive symptoms and sleep restoration; cannabis psychoeducation and harm-reduction/cessation support; sleep interventions.
Psychological: psychoeducation about psychosis; collaborative formulation in plain language; CBT for psychosis elements when engagement allows; motivational work for cannabis.
Social/family: family psychoeducation to lower EE and align a shared illness model; involve sister as support; education/university liaison when stable; practical supports.
Cultural/meaning: explore illness explanations (spirits/system) with curiosity (CFI-style); do not ridicule; negotiate a shared care plan that respects meaning while offering medical model as additional frame.
Risk: full suicide/violence/vulnerability assessment; safety plan; intensity of follow-up matched to risk and supports; least-restrictive setting that is safe.
Review: rewrite formulation after abstinence attempt, treatment response, and collateral.[1][4][5]

Common errors

References

[1]Macneil CA, Hasty MK, Conus P, et al. Is diagnosis enough to guide interventions in mental health? Using case formulation in clinical practice BMC Med, 2012.PMID 23016556
[2]Owen G What is formulation in psychiatry? Psychol Med, 2023.PMID 36878884
[3]Engel GL The need for a new medical model: a challenge for biomedicine Science, 1977.PMID 847460
[4]Lewis-Fernández R, Aggarwal NK, Lam PC, et al. Feasibility, acceptability and clinical utility of the Cultural Formulation Interview: mixed-methods results from the DSM-5 international field trial Br J Psychiatry, 2017.PMID 28104738
[5]Lewis-Fernández R, Aggarwal NK, Bäärnhielm S, et al. Culture and psychiatric evaluation: operationalizing cultural formulation for DSM-5 Psychiatry, 2014.PMID 24865197