Clinical Competency and Capacity Assessment
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Direct answer
Capacity is a clinical judgement made at the bedside; competency is a legal determination made by a court — and the everyday work is capacity. The standard framework is the four abilities model of Appelbaum and Grisso: the patient must understand the relevant information, appreciate that it applies to their own situation, reason with it by comparing options and consequences, and communicate a consistent choice. Capacity is decision-specific and time-specific — a person may keep capacity to make a will while lacking it for dialysis refusal, and fluctuating delirium demands reassessment — and it is presumed until shown otherwise. India's Mental Healthcare Act 2017 pushes the same way: presumed capacity, supported decision-making, advance directives and nominated representatives replacing guardianship-style logic.
What you must remember
- The four abilities, in order: understand the information, appreciate its personal application, reason through the options, express a choice — reciting this sequence verbatim is the viva answer.
- Decision-specific and time-specific: capacity for a will differs from capacity for dialysis refusal; a delirious or fluctuating patient must be retested at their best time of day.
- Presumption with reversal of proof: every adult is presumed to have capacity; the burden lies on the clinician to demonstrate incapacity, never on the patient to prove capacity.
- Sliding-scale principle: the more serious the consequences of a refusal, the more rigorous the assessment demanded — though the criterion remains the abilities, not the decision's popularity.
- Unwise is not incapable: a refusal that seems bizarre (declining dialysis for religious reasons) does not itself establish incapacity — odd choices with understood consequences can be capacitous.
- Cognitive scores do not equal capacity: a low MMSE suggests, but does not decide, incapacity; the structured instrument is the MacCAT-T, used alongside, not instead of, clinical judgement.
- MHCA 2017 machinery: presumption of capacity unless proven otherwise, advance directives registered with the Mental Health Review Board, nominated representatives, and supported rather than substituted decision-making.
- Enhance before you assess: treat pain, delirium, depression and hypoxia; use interpreters; give information in digestible form — many "incapacities" are untreated conditions or poor communication.
The four abilities at the bedside
Consider a 72-year-old man with gangrenous foot refusing amputation, referred "to certify competency". The assessment is an interview, not a form. Understanding: asked what the doctors said, he explains that the foot is dead, infection is spreading, and the operation removes it below the knee — the facts held in his own words. Appreciation — the usual failure point: does he believe this applies to him? Yes, it is his foot and his infection — no dissociative escape here ("the reports belong to someone else"). Reasoning: he compares options — amputation with a prosthesis versus death from sepsis within weeks — ("I have seen my brother die after an operation; at my age I accept the other outcome"). Expressing a choice: the refusal is stable across two interviews, a day apart, family present and absent.
All four abilities intact: he has capacity for this decision, whatever the surgical team feels about its wisdom — documented precisely, the note protects both patient and clinician. Contrast the mirror case: a woman in alcoholic withdrawal believing the X-ray films show the nurses' plot; she fails appreciation, and her refusal is deferred while the delirium is treated and capacity reassessed seventy-two hours later.
How the exam frames it
Two contrasts carry the questions. Capacity-versus-competency (clinical versus legal) appears as a straightforward discriminator. The four-abilities model appears as a matching list against distractors like "intelligence" or "good outcome of the decision" — the exam insists that the quality of the choice is never a criterion. The MHCA 2017 angle is distinctly Indian and increasingly tested — know its machinery (presumption, directives, representatives, Board) by name. Finally, the psychiatric conditions that impair capacity (delirium, dementia, psychosis, severe depression with nihilism) surface as stems asking which ability is lost — depression typically attacks appreciation and reasoning, delirium attacks understanding first.
Frequently asked questions
What are the four abilities assessed in clinical capacity?
Understanding the relevant information, appreciating that it applies to oneself, reasoning by comparing options and consequences, and communicating a stable choice — the Appelbaum and Grisso model.
Is capacity a permanent, global status?
No — it is decision-specific and time-specific, must be presumed in every adult, and requires reassessment when conditions such as delirium or depression fluctuate.
Can a capacitous patient make an unwise medical refusal?
Yes — an unusual or risky choice, made with understanding, appreciation and reasoning, remains capacitous; the decision's wisdom is not a capacity criterion.
What is the MacCAT-T?
The MacArthur Competence Assessment Tool for Treatment — a structured interview operationalising the four abilities, used to supplement but not replace clinical judgement.
How does the Mental Healthcare Act 2017 reshape capacity in India?
It presumes capacity unless proven otherwise, mandates supported decision-making, and provides advance directives registered with the Mental Health Review Board and nominated representatives — replacing substituted judgement as the default.