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Talk to the Elephant: Design Learning for Behavior Change · 8 of 13
Talk to the Elephant: Design Learning for Behavior Change
learning-design CRITICAL

Mapping COM-B to Intervention Types and BCTs

Talk to the Elephant: Design Learning for Behavior Change Julie Dirksen
behaviour-change-wheel bct-taxonomy intervention-types com-b-mapping

Key Principle

The Behaviour Change Wheel (BCW) is a three-level decision hierarchy:

Level 1: COM-B Diagnosis (what sub-factor is deficient?) Level 2: Intervention Type (what category of action addresses it?) Level 3: BCT Selection (which specific evidence-coded technique?)

The Nine Intervention Types and Their COM-B Targets:

Intervention Type Primary COM-B Target Mechanism
Education Psychological Capability (Reflective) Increase knowledge or understanding
Training Physical & Psychological Capability Develop skills through practice
Persuasion Reflective Motivation Influence reasoning/emotion through communication
Modeling Physical & Social Opportunity, Automatic Motivation Demonstrate behaviors for imitation
Incentivization Reflective & Automatic Motivation Reward or create expectation of reward
Coercion Reflective & Automatic Motivation Threaten punishment or create expectation of punishment
Restriction Physical Opportunity Use rules to reduce opportunity for the unwanted behavior
Environmental Restructuring Physical & Social Opportunity Change physical or social context
Enablement Psychological Capability, Physical & Social Opportunity Reduce barriers by increasing ability or support

Critical constraint: Each intervention type can only reach the COM-B sub-factors it targets. Education cannot fix a Physical Opportunity problem. Restriction cannot produce intrinsic motivation. Selecting the wrong intervention type produces a well-executed solution to the wrong problem.

Why This Matters

The BCT taxonomy (93 numbered, evidence-coded techniques) is the tactical implementation layer. BCT selection happens AFTER intervention type selection, which happens AFTER COM-B diagnosis. The most common design error is BCT selection without diagnostic grounding — reaching for familiar techniques (e.g., goal-setting, gamification) before identifying whether they target the actual root cause.

Education and Training are the most frequently prescribed intervention types and the most frequently misapplied. Education (increasing knowledge/understanding) is appropriate only when Psychological Capability — specifically knowledge or understanding — is the actual bottleneck. When the bottleneck is elsewhere, Education has no effect.

The COM-B → Intervention Type Mapping

COM-B Sub-Factor Appropriate Intervention Types
Physical Capability Training, Enablement
Psychological Capability Education, Training, Enablement, Modeling
Physical Opportunity Environmental Restructuring, Enablement, Restriction
Social Opportunity Modeling, Environmental Restructuring (social), Enablement
Reflective Motivation Education, Persuasion, Incentivization, Coercion
Automatic Motivation Modeling, Environmental Restructuring, Incentivization, Training (habit-forming)

The BCT Taxonomy — Key Clusters

BCTs are numbered in clusters (1.x through 16.x). The clusters most relevant to learning design:

  • 1.x Goals and Planning: 1.1 Goal Setting (behavior), 1.4 Action Planning, 1.8/1.9 Commitment/Behavioral Contract
  • 2.x Feedback and Monitoring: 2.1 Monitoring by Others, 2.4 Self-Monitoring
  • 3.x Social Support: 3.1 Social Support (unspecified), 3.2 Social Support (practical)
  • 4.x Shaping Knowledge: 4.1 Instruction on Performance, 4.4 Behavioral Experiments
  • 5.x Natural Consequences: 5.1 Salience of Consequences, 5.2 Pros/Cons, 5.3 Anticipated Regret
  • 6.x Comparison of Behavior: 6.1 Demonstration of Behavior, 6.2 Social Comparison, 6.3 Information About Others' Behavior
  • 7.x Associations: 7.1 Prompts/Cues, 7.2 Cue Salience
  • 8.x Repetition and Substitution: 8.1 Behavioral Practice, 8.2 Behavior Substitution, 8.3 Habit Formation, 8.4 Habit Reversal
  • 9.x Comparison of Outcomes: 9.1 Credible Source
  • 11.x Regulation: 11.1 Pharmacological Support (N/A for L&D)
  • 12.x Antecedents: 12.1 Restructuring Physical Environment, 12.2 Restructuring Social Environment
  • 13.x Identity: 13.1 Identification of Self as Role Model, 13.2 Framing/Reframing, 13.3 Incompatible Beliefs, 13.5 Identity Associated with Changing Behavior (Valued Self)
  • 15.x Self-Belief: 15.1 Verbal Persuasion re: Capability, 15.3 Focus on Past Success
  • 16.x Covert Learning: 16.2 Anticipated Regret (imaginal)

Good Examples

Correct BCT selection chain (Chapter 14 case study — alt text accessibility): COM-B analysis finds: Psychological Capability gap (designers don't know the standard) + Physical Opportunity gap (no alt text field in current workflow) + Automatic Motivation gap (no habit, behavior not yet automatic) + Social Opportunity gap (no team norm). Selected intervention types: Education (4.1 Instruction) + Environmental Restructuring (12.1 add alt text field) + Training (8.3 Habit Formation through practice) + Modeling (6.1 Demonstration + 13.1 Role Model identification). This is a multi-BCT solution because there are multiple COM-B gaps.

Wrong BCT selection (common error): Seeing non-compliance and immediately selecting 1.1 Goal Setting + 2.4 Self-Monitoring assumes the gap is in Reflective Motivation (the person doesn't have a goal and isn't tracking). If the actual gap is Physical Opportunity (the environment doesn't support the behavior) or Automatic Motivation (no habit), goals and self-monitoring will produce initial effort that decays when Rider willpower runs out.

Counterpoints

Restriction sounds like a powerful lever but it only targets Physical Opportunity — it reduces the ability to perform the unwanted behavior, but leaves motivation intact. When motivation is high and the person is resourceful, Restriction produces workarounds. It should be paired with interventions that address the motivational root cause.

Coercion (consequences for non-compliance) produces external regulation — the least autonomous form of motivation. Behavior continues only as long as enforcement continues. Coercion is appropriate for irreducible safety-critical minimums, not for behaviors requiring internalized judgment and discretion.

Incentivization applied to already-intrinsically-motivated behaviors triggers the Overjustification Effect — introducing external rewards for intrinsically motivated behaviors undermines intrinsic motivation when the rewards are removed. See motivation-and-sdt.md.

Key Quotes

"Just picking BCTs that appeal to you, rather than those matched to the root cause, is likely to be ineffective." — Julie Dirksen, Chapter 8: Mapping to Solutions

Rules of Thumb

  • Never select a BCT before selecting an intervention type. Never select an intervention type before completing COM-B diagnosis.
  • For each identified COM-B gap, select the corresponding intervention type(s) from the mapping table.
  • Most real behavior change problems have multiple COM-B gaps and therefore require multiple BCTs.
  • BCT 4.1 (Instruction on Behavior) is the most commonly over-used BCT — it addresses only knowledge-level Psychological Capability.
  • When BCTs from Chs. 9–12 conflict (e.g., both BCT 1.8 Commitment AND BCT 13.1 Role Model seem relevant), select based on which COM-B sub-factor is most deficient.

Related References