How Capacity Assessments Work in England, Wales and Scotland

Northern Ireland note: The Mental Capacity Act (Northern Ireland) 2016 is being implemented in phases. Phase One covers deprivation of liberty, research, and money and valuables. Do not assume the full Act is in force for every healthcare decision.

On placement, you may hear someone say:

“We need to assess their capacity.”

This might happen when a patient refuses treatment, wants to leave hospital or is involved in a complicated discharge decision. A few questions are asked, staff discuss the situation and something is documented in the notes, but what is actually being assessed?

In England and Wales, capacity assessments are governed by the Mental Capacity Act 2005. Scotland has a separate framework under the Adults with Incapacity (Scotland) Act 2000. Although both systems aim to protect autonomy, their terminology and legal processes are not identical.

This overview mainly explains the Mental Capacity Act framework used in England and Wales, with important Scottish differences highlighted separately.

When Is a Capacity Assessment Needed?

Adults must be presumed to have capacity unless there is a genuine reason to doubt it. A patient should not be assessed simply because they disagree with staff, refuse treatment or make a decision that others consider unwise.

An assessment may be needed when a person’s behaviour, communication, diagnosis or clinical condition raises reasonable concern about their ability to make a particular decision.

Examples include:

• delirium affecting a patient’s understanding of treatment
• dementia affecting a complex discharge decision
• a brain injury affecting the ability to weigh risks
• severe mental illness affecting a specific treatment decision
• intoxication or reduced consciousness
• difficulty understanding the consequences of leaving hospital

Capacity is both decision-specific and time-specific. A person may be able to decide what they want to eat but lack capacity to consent to complex surgery. They may also lack capacity during an episode of delirium and regain it after treatment.

Start by Supporting the Patient

Before concluding that someone cannot make a decision, healthcare professionals must take practicable steps to help them decide.

This might include:

• using plain language
• breaking information into smaller parts
• providing an interpreter or communication aid
• treating pain, breathlessness or distress
• choosing a quieter environment
• involving someone familiar to the patient
• allowing additional time
• assessing at a better time of day where possible

The person does not need to remember every clinical detail or explain the decision using medical terminology. They need enough relevant information to make the particular decision.

The Two-Stage Test

Under the Mental Capacity Act 2005, a person lacks capacity only when both stages of the legal test are satisfied.

Stage One: Is There an Impairment or Disturbance?

There must be an impairment of, or disturbance in, the functioning of the person’s mind or brain.

Possible examples include:

• dementia
• delirium
• stroke or brain injury
• learning disability
• severe mental illness
• intoxication
• reduced consciousness
• cognitive effects of acute illness

A diagnosis alone does not prove that someone lacks capacity.

Stage Two: Does the Impairment Make the Person Unable to Decide?

The assessor must establish whether the impairment or disturbance causes the person to be unable to make the particular decision.

A person is unable to make the decision if they cannot do one or more of the following:

• understand the relevant information
• retain it long enough to make the decision
• use or weigh it as part of the decision-making process
• communicate the decision by any means

There must be a connection between the impairment and the inability to decide. The conclusion is reached on the balance of probabilities, meaning it is more likely than not that the person lacks capacity for that decision at that time. These requirements come directly from sections 2 and 3 of the Mental Capacity Act 2005.

What Does an Assessment Look Like?

Most capacity assessments look like structured conversations rather than examinations.

For example, a clinician might ask:

“What have you been told about the treatment?”

“What do you understand the treatment is for?”

“What might happen if you have it?”

“What might happen if you decide not to have it?”

“What is most important to you when making this decision?”

The purpose is not to make the patient agree with the healthcare team. It is to establish whether they can understand and weigh the relevant information.

A person with capacity is legally entitled to make an unwise or risky decision. Refusing recommended treatment does not, by itself, prove incapacity.

Capacity Can Fluctuate

Capacity may change because of delirium, infection, medication, pain, fatigue, intoxication or changes in mental health.

Where the decision is not urgent and the person may regain capacity, it may be appropriate to delay it. Clinicians should also consider whether communication, alertness or concentration is better at a particular time.

However, there is no universal “decision window,” and NICE does not impose a blanket legal duty to assess every patient at a particular time of day. The requirement is to take reasonable steps to support decision-making and consider whether the decision can safely wait. NICE NG108 provides detailed guidance on supporting and assessing capacity.

“Sundowning” may affect some people with dementia, but it should not be assumed to affect everyone.

Who Carries Out the Assessment?

The person responsible for the treatment, care or decision will usually assess capacity in relation to that decision.

For example:

• a surgeon may assess capacity to consent to surgery
• a nurse may assess capacity for a nursing care decision
• a therapist may assess capacity relating to rehabilitation
• an appropriately experienced professional may assess capacity concerning accommodation or discharge

More serious or contested decisions require a proportionately detailed assessment by someone with suitable experience. Specialist input may be helpful, but a psychiatrist is not automatically required for every capacity assessment.

Student nurses should not normally undertake complex formal assessments independently. However, students can observe conversations, support communication, report changes in cognition and contribute relevant observations under supervision.

Documenting a Capacity Assessment

Documentation should clearly identify:

• the exact decision being assessed
• why capacity was questioned
• the impairment or disturbance identified
• what support was provided
• the relevant information explained
• how the person performed in relation to understanding, retaining, using or weighing, and communicating
• how the impairment caused any inability to decide
• the conclusion and when the assessment occurred

Some organisations use forms called “MCA1” and “MCA2,” but these names are not nationally standardised. Forms and electronic templates vary between NHS organisations.

Simply writing “patient lacks capacity” is not enough.

What Happens When a Patient Lacks Capacity?

When a person lacks capacity, the next step is not automatically to proceed with whatever professionals prefer.

In England and Wales, any act or decision made on the person’s behalf must be in their best interests. The decision-maker must consider:

• whether the person may regain capacity
• how the person can participate
• their past and present wishes
• their beliefs and values
• any relevant advance decision
• whether a Health and Welfare Lasting Power of Attorney or court-appointed deputy has authority
• the views of family members, carers and others interested in their welfare
• less restrictive options

Best interests are broader than clinical benefit alone. However, the test is not simply “What would the patient have chosen?” Their likely wishes are extremely important, but they form part of the full statutory best-interests process.

Urgent necessary treatment may sometimes proceed when a patient lacks capacity, but staff must still check for legally relevant arrangements such as a valid and applicable Advance Decision to Refuse Treatment or an authorised Health and Welfare LPA.

The Role of an IMCA

An Independent Mental Capacity Advocate provides statutory safeguards for certain people who lack capacity in England and Wales.

For serious medical treatment or certain longer-term accommodation decisions, an IMCA will generally be required when:

• the person lacks capacity for the decision
• there is no appropriate unpaid person, such as a relative or friend, available to consult
• no authorised attorney or deputy can make the decision
• the decision is not so urgent that it cannot wait

An IMCA does not make the final decision. They support and represent the person, gather information, examine alternatives and ensure that the person’s rights, wishes and values are considered.

IMCAs may also be involved in some care reviews and safeguarding cases. Different rules apply to these referrals, and an IMCA may sometimes be instructed even where family members are available.

Important Differences in Scotland

Scotland does not use the Mental Capacity Act or its statutory IMCA framework.

The Adults with Incapacity (Scotland) Act 2000 defines incapacity differently and is based on principles including:

• benefit to the adult
• the least restrictive option
• consideration of past and present wishes
• consultation with relevant people
• encouraging the adult to use and develop existing skills

For non-emergency medical treatment, authority may require a Section 47 certificate completed by a doctor or another appropriately trained and authorised healthcare professional. Scottish practitioners should follow the Adults with Incapacity medical treatment code of practice.

Independent advocacy may still be available in Scotland, but it should not automatically be described as the MCA’s IMCA service.

Placement Tips for Student Nurses

If you are concerned about a patient’s decision-making:

1. Identify the exact decision involved.

2. Do not assume incapacity because of diagnosis, age, refusal or an unwise choice.

3. Consider whether communication, pain, delirium or the environment can be improved.

4. Report your observations clearly to your supervising nurse.

5. Document factual observations rather than making unsupported conclusions.

6. Escalate urgent safety or safeguarding concerns promptly.

7. Follow local policy and remain within your competence.

A useful way to remember the process is:

Support first. Assess the specific decision. Establish the cause. Document the evidence.

What to remember

Capacity assessments are not designed to remove control from patients. Their purpose is to protect the right to make personal decisions while providing lawful safeguards when someone genuinely cannot decide for themselves.

For student nurses, the most important principles are that capacity is presumed, decision-specific and time-specific. A diagnosis does not establish incapacity, and a decision does not have to appear sensible to be valid.

References

Department for Constitutional Affairs. Mental Capacity Act 2005 Code of Practice. GOV.UK.

Mental Capacity Act 2005. UK Legislation.

NICE. (2018). Decision-making and mental capacity (NG108). NICE.

Scottish Government. Adults with Incapacity: Overview to Assessing Capacity. Scottish Government.

Scottish Government. Adults with Incapacity: Code of Practice for Medical Practitioners. Scottish Government.