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Learn about implementation science theories, models and frameworks and their application to primary health care and immunization
Comprehensive reference guide for using implementation science theories, models and frameworks in primary health care and immunization

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COM-B and the Behaviour Change Wheel

Lesson 3 of 8 · about 10 minutes

Goal Diagnose one behaviour and match it to the right kind of intervention.

Every result rests on someone doing something. COM-B says a behaviour needs three conditions: capability, opportunity and motivation. Start by naming the behaviour precisely: who does what, when and where.

Weak: "Caregivers should complete immunization." Strong: "Caregivers bring their child back for Penta2 at 10 weeks."

CapabilityPsychologicalknows, remembersPhysicalhas the skill, strengthOpportunityPhysicaltime, money,stock, placeSocialnorms, family, leadersMotivationReflective: beliefs, plansAutomatic: habits, feelingsBehavioure.g. returns
COM-B. All three conditions must be present. Capability and opportunity also shape motivation, and doing the behaviour changes all three over time.

Match the Diagnosis to a Function

The Behaviour Change Wheel surrounds COM-B with nine intervention functions. Choose functions to match the weakest component.

Weak componentFunctions to tryNigerian example
CapabilityEducation, trainingExplain the three-dose schedule at Penta1 so the caregiver knows when to return.
OpportunityEnvironmental restructuring, enablementHold outreach on market day. Send a town-announcer reminder.
MotivationPersuasion, modelling, incentivisationA respected mother shows her child's completed card at a community meeting.

Education will not fix a cancelled session, because a cancelled session is an opportunity problem. One function often serves several components. A return date written on the card prompts memory, and the Behaviour Change Wheel classes prompts as environmental restructuring.

Use It on MondayWrite your target behaviour as "who does what, when, where". Ask three caregivers or staff what makes it hard. Circle the weakest of C, O and M.

Go deeper: the full wheel (9 functions, 7 policy categories) · Theoretical Domains Framework