Module 10 · The science in depth · Supported by multiple studies

The intention–behaviour gap in research

How big the gap is, and which strategies close it.

6 min read · Level: Advanced · Free — no account needed to read

The problem it solves

How big is the gap between intending and doing, and what closes it?

The concept

A meta-analysis of experiments found that changing intentions by a medium-to-large amount changed behaviour by only a small-to-medium amount. For physical activity, close to half of people who intended to be active didn’t follow through.

Research groups the problems into three: failing to get started, getting derailed once started, and not following through to completion. Different strategies suit each — if–then plans and cues for starting, monitoring and coping plans for staying on track, clear endpoints for finishing.

This is why so much of habit science focuses on what happens after the decision — the volitional phase — rather than on persuading people to want something more.

Why it matters

It explains why motivation-only approaches disappoint, and why planning, cues and environment design carry so much of the weight in behaviour change.

Supported by multiple studies: Many studies, often pooled in reviews or meta-analyses, point the same way. It still works better for some people and situations than others.

See it happen

A workplace wellness programme runs inspiring talks but sees little change in behaviour.

The ordinary first approach

The talks weren’t inspiring enough.

With the idea

The research suggests adding planning, prompts and easier options to the talks, since intentions were probably already high.

What changed

The focus moved from wanting to doing.

Easy to get wrong

• Measuring success by intentions rather than behaviour.
• Using the same strategy for starting, staying on track and finishing.
• Assuming people who don’t act don’t care.

Try it now: Diagnose your gap

1. Pick one intention you haven’t acted on.
2. Ask whether it fails at starting, staying on track, or finishing.
3. Choose one matching strategy and try it.

Apply it to one of your habits

For one of your habits, where does it usually fall through — starting, staying on track, or finishing?

Reflect

• Which part of the gap is widest for you?

Go deeper — evidence & sources

• Webb & Sheeran (2006). Does changing behavioral intentions engender behavior change? A meta-analysis of the experimental evidence. Psychological Bulletin. doi:10.1037/0033-2909.132.2.249
• Sheeran & Webb (2016). The Intention–Behavior Gap. Social and Personality Psychology Compass. doi:10.1111/spc3.12265
• Rhodes & de Bruijn (2013). How big is the physical activity intention–behaviour gap? A meta-analysis using the action control framework. British Journal of Health Psychology. doi:10.1111/bjhp.12032
• Heckhausen & Gollwitzer (1987). Thought contents and cognitive functioning in motivational versus volitional states of mind. Motivation and Emotion. doi:10.1007/BF00992338