Motivational interviewing

What is motivational interviewing?

Motivational interviewing is a way of talking about change. The National Institute for Health and Care Excellence defines it as helping people explore and resolve ambivalence towards change.

Being in two minds is the point of it. Miller and Rollnick describe it as a tool for when someone is reluctant or ambivalent about a change.

Nobody argues you into anything. NHS Education for Scotland says the approach does not apply coercive methods to impose change.

Sources: NICE NG181, Miller & Rollnick 2009, NES: Matrix MI guide

The four tasks

The conversation moves through four tasks. Miller and Rollnick name them as engaging, focusing, evoking and planning.

They used to be called processes. The fourth edition of their book renamed them tasks in 2023.

Miller and Rollnick also name four words for its spirit. They are partnership, acceptance, compassion and empowerment.

Empowerment is the newest of the four. They broadened the earlier idea of evocation, to stress your own strengths and your autonomy.

Sources: Miller & Rollnick 2023, MINT: understanding MI

Why it is a style, not a therapy

Motivational interviewing is not a school of therapy. Miller and Rollnick call it a guiding style for strengthening your own motivation to change.

They are blunt about its reach. They write that it would make little sense to run a practice offering only this.

So you are most likely to meet it inside other work. Miller reports that its commonest use now is alongside other methods, such as cognitive behavioural therapy.

Sources: Miller & Rollnick 2009, Miller 2023

What sessions look like

It is meant to be short. Miller and Rollnick write that they would not expect it to fill more than a session or two.

Research has run it longer than that. A 2023 Cochrane review found most of its studies used a single session, and some used up to nine.

Length varies a great deal. The same review reports sessions from ten minutes to well over two hours.

Sources: Miller & Rollnick 2009, Schwenker et al. 2023

Who it might suit

It can be a good fit if you:

• Want a change and keep putting it off
• Find that part of you wants it and part of you does not
• Bristle when someone tells you what you ought to do
• Know what would help and are not doing it
• Have been pushed towards a change by somebody else
• Would rather reach your own reasons before you act

It may suit you less well if you have already decided and want to get on with it. Miller and Rollnick note that people who are ready for change do not need it. They add that it may even slow such a person down.

If the change you want is a goal outside mental health, coaching may fit better. Coaching is not a therapy.

Source: Miller & Rollnick 2009

If your question is about addiction

Much of the research on this approach is about substance use. A 2023 Cochrane review of it pooled 93 trials.

Our addiction pages put specialist services first, and talking support alongside them. Every service listed there is free.

Source: Schwenker et al. 2023

The evidence

The evidence base is wide and mostly weak. A 2018 review of 104 reviews graded most of the pooled evidence as low or very low quality.

Little of it reached moderate quality. Those authors found moderate quality evidence of small, mainly short-term benefits in eleven of their 155 comparisons.

Physical activity shows the same shape. A 2024 review in The BMJ pooled 97 trials and found more activity than weaker comparisons, at low certainty.

Those gains did not last. Its authors report that evidence of an effect beyond one year was lacking. They also found no difference against comparisons of similar intensity.

On substance use, Cochrane is cautious. Its authors say the approach may make little to no difference against usual care or another active treatment.

They hold that view loosely. The review reports moderate to no confidence in its evidence, and expects future studies to change its conclusions.

NICE names motivational interviewing in several of its guidelines. NG98 says to consider it when hearing aids are first discussed. NG252 says to consider it to encourage lifelong change around physical activity.

NICE has also declined to recommend it. PH49, its guideline on individual behaviour change, says the evidence made it impossible to recommend the approach.

If you are weighing up a few options, our guide to the different approaches sets them side by side.

Sources: Frost et al. 2018, Zhu et al. 2024, Schwenker et al. 2023, NICE NG98, NICE NG252, NICE PH49