Why strong clinical data does not always change HCP behaviour

Expert insight by Diana Heimberg, CELforPharma faculty member of Applied Behavioural Science for HCP & Patient Engagement

Why evidence alone is rarely enough

What are heuristics & cognitive biases and why do they matter for HCP communication?

Heuristics are mental shortcuts the brain uses to make fast, efficient decisions without requiring full conscious analysis. They develop through experience and are deeply embedded in how all humans, including clinicians, process information and make judgements.

Cognitive biases are the systematic errors in thinking that can result from these shortcuts. In a clinical context, they influence how an HCP reads a study summary, evaluates a treatment option, or responds to a recommendation from a peer or professional body.

For medical affairs and marketing professionals, identifying which heuristics and cognitive biases are active in a given situation makes it possible to frame evidence in a way that is both scientifically accurate and behaviourally effective.
 

Six cognitive biases that directly affect HCP communication in pharma

These six are among the most well-evidenced and practically applicable for pharma marketing and medical affairs teams working across European markets.
 

1.    Primacy and Recency Effect

HCPs, like all people, remember information that comes first and information that comes last. What sits in the middle of a message is the most likely to be forgotten. Restructuring a clinical claim so the most important finding leads, and the supporting context follows, increases recall and impact without altering the underlying data.

• Before: "A meta-analysis of studies spanning 30 years showed that 3 out of 4 metastatic melanoma patients die within 12 months."
• After: "3 out of 4 metastatic melanoma patients die within 12 months, according to a meta-analysis spanning 30 years."
   

2.    Ratio Preference Bias

HCPs understand risk and clinical outcomes more intuitively when data is expressed as a natural ratio rather than a percentage. The same statistic lands differently depending on how it is presented. Translating percentages into ratios makes data feel more concrete and easier to apply in a clinical context. The underlying data is identical. The way the brain receives it is not.

• Before: "According to a meta-analysis of studies from 1975 to 2005, the one-year survival rate of metastatic melanoma was 25%."
• After: "A meta-analysis of studies spanning 30 years showed that 3 out of 4 metastatic melanoma patients die within 12 months."
   

3.    Social Proof

HCPs are significantly influenced by the behaviour and recommendations of respected peers and professional bodies. A communication that references what colleagues in the same specialty are doing, or what a guideline body recommends, is more likely to prompt consideration than a direct call to action presented in isolation.

• Before: "Prescribe RX for your patients with diabetes."
• After: "The ADA recommends RX for your patients with diabetes."
   

4.    Effort Bias

When evaluating options, people consistently favour those that appear to require less effort. In HCP communications, language that signals simplicity and ease, words like "straightforward," "in a single step," or "without additional burden," tends to outperform language that implies complexity or process.

• Example: "Getting your patients approved has never been easier. Apply online in minutes and receive a response quickly, so you can focus on what matters most."
   

5.    Numerosity Effect

The brain responds to the size of a number independently of the unit it represents. Larger numbers feel more significant, even when the quantity they describe is the same. Expressing clinical outcomes in smaller units, where it is accurate and appropriate to do so, can increase the perceived weight of the evidence.

• Before: "Patients in the clinical trial had sustained relief for 2 years."
• After: "Patients in the clinical trial had sustained relief for 24 months."
   

6.    Ingroup Bias

Professional identity is a powerful driver of clinical decision-making. HCPs are more receptive to information that is positioned as relevant to their specific specialty and peer group. A communication that speaks to what cardiologists, or oncologists, or endocrinologists specifically are doing carries more weight than a general recommendation.

• Before: "Prescribe RX for your patients with diabetes."
• After: "RX is the #1 most prescribed SGLT2 inhibitor among endocrinologists."
   

How to choose the right heuristic for your message

The most effective approach is to start with the behavioural barrier rather than the heuristic. Using the COM-B framework, which identifies Capability, Opportunity and Motivation as the three core drivers of behaviour, it is possible to map the barrier and select the most appropriate framing technique.

• Capability barriers (the HCP lacks knowledge or understanding): Primacy/recency effect, numerosity effect
• Opportunity barriers (the context makes the behaviour harder): Effort bias, social proof, ingroup bias
• Motivation barriers (the HCP lacks sufficient reason to act): Loss aversion, ingroup bias, social proof
  
   

Download: The Pharma Message Reframing Guide

Six evidence-based heuristics. Before-and-after message examples. A practical framework for selecting the right approach based on the behavioural barrier you are trying to address.

Developed for medical affairs and marketing professionals in the pharmaceutical industry who want to apply behavioural science principles to their communications in a rigorous and practical way.

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