Dual Process Theory (DPT) in Clinical Reasoning
Type 1 (Intuitive) vs Type 2 (Analytical) Thinking
Type 1: Fast, automatic, unconscious, heuristic-driven. Used ~95% of the time. Efficient but vulnerable to bias.
Type 2: Slow, deliberate, conscious, rule-based. Reliable but effortful. Key to debiasing.
The brain defaults to Type 1 unless overridden (executive override / decoupling).
Paramedic Example (from Croskerry)
A paramedic sees a young patient with chest pain and immediately thinks “anxiety” (Type 1 framing). Later reflection (Type 2) reveals risk factors for pulmonary embolism → correct diagnosis.
Origins of Cognitive Bias
Four Main Sources (Stanovich classification)
| Source | Description | Paramedic Example |
|---|---|---|
| Hard-wired (evolutionary) | Anchoring, availability, representativeness | Assuming all “frequent flyers” have nothing serious |
| Emotionally regulated | Fear, anger, disgust toward patient types | Aversion to patients with substance use → incomplete assessment |
| Over-learned | Repeated exposure in practice | Assuming “psych” patient has no medical issue |
| Implicitly learned | Hidden curriculum / workplace culture | Subtle bias toward elderly patients picked up from mentors |
Affective Bias & Emotional Influences (Croskerry 2010)
Key Affective Biases in Paramedicine
- Fundamental Attribution Error (FAE): Blaming patient disposition rather than situation (e.g., “drug seeker” instead of genuine pain)
- Countertransference: Past experiences colour current patient interaction
- Chagrin factor: Avoiding unpleasant diagnoses to spare emotional discomfort
- Outcome bias: Judging decision quality by outcome rather than process
“The emotional temperature of the doctor plays a substantial part in diagnostic failure and success.” — Horton (2007)
Paramedic Case: Tired paramedic attributes chest pain in a known opioid user to “drug seeking” (FAE + affective bias) → misses pulmonary embolism.
High-Risk Situations for Bias in Paramedicine
| Situation | Likely Biases |
|---|---|
| End of long shift / fatigue / sleep deprivation | All biases increase |
| Patient handed off from another crew | Diagnosis momentum, framing |
| Patient you dislike or like too much | Affective bias, countertransference |
| Psychiatric history or “frequent flyer” | Psych-out error, FAE |
| Time pressure / cognitive overload | Premature closure, anchoring |
Strategies to Increase Safety & Quality of Reasoning
Educational Strategies
- Bias inoculation training
- Simulation with deliberate error traps
- Metacognition / reflection training
Workplace Strategies
- Slowing down when fatigued
- Consider-the-opposite
- Structured data acquisition (full history/exam)
- Supportive environments (reduce overload)
Forcing Functions (Croskerry)
- Cognitive forcing strategies (e.g., always rule out worst-case)
- Checklists & ROWS (Rule Out Worst Scenario)
- Decision support tools
Transtheoretical Model of Change for Paramedics
Apply to your own journey to becoming debiased:
- Precontemplation: “Biases don’t affect me”
- Contemplation: “Maybe I should learn about this”
- Preparation: “I’ll start reflecting after each shift”
- Action: “I now pause and use consider-the-opposite on every chest pain”
- Maintenance: “Debiasing is now automatic in my practice”
Metacognition & Reflective Practice
Practical Reflection Questions (after every shift)
- Did I default to Type 1 too quickly?
- Was I influenced by emotion or fatigue?
- Did I use a forcing function?
- What would I do differently next time?
“The ability to engage in purposeful, self-regulatory judgment” — Critical Thinking Definition