Cognitive Bias - Understanding Diagnosis - 3
What do you see? A woman walking by or maybe… the face of a man?
Medicine, the noblest of professions , is primarily a cognitive profession. Physicians see patients with vague, undifferentiated symptoms and have to rapidly and accurately arrive at a diagnosis and management plan. Unfortunately, despite the best efforts, errors creep in Cognitive biases, rather than knowledge deficits, are thought to be the primary cause of these errors.
Bias is an inclination or outlook to present or hold a partial perspective, often accompanied by a refusal to consider the possible merits of alternative points of view. Biases can be learned implicitly within cultural contexts. Biased means one-sided, lacking a neutral viewpoint, or not having an open mind.
Bias,Rationality and intelligence are different. You may be tempted to think that these biases don’t affect you, even if you can recognize them in others. The blind spot bias describes the tendency to fail to recognize one’s own errors and it appears to be hardwired into the human mind. Most expert cognition relies on heuristics, developed over years of experience and yet this comes along with bias. Pattern recognition is efficient and often extremely accurate, but unfortunately there are some situations in which it can fail :
The pattern might be misidentified. A rash that looks a lot like classic shingles might actually be an unlikely distribution of poison oak.
The practitioner may not have seen enough cases to develop an accurate pattern. He may have seen 10,000 sore throats and developed a very rapid diagnostic pattern recognition approach, but if he has never seen a case of Lemierre’s disease, he will miss that pattern.
The pattern may not be classic. Diseases that present very early, before the classic pattern develops, or diseases for which the classic pattern significantly overlaps with other diseases are likely to be missed.
Vigilance over the shortcomings of pattern recognition may become compromised. For example, a physician might recognize GERD by its pattern, but remain constantly vigilant for a myocardial infarction with a similar presentation. However, after 2 horrendous resuscitations, that vigilance may be compromised, resulting in misdiagnosis.
We will continue with the descriptions of the common cognitive errors in Medicine in the next part, Kinds of cognitive errors - Understanding diagnosis - 4
