"And checklists lack flexibility. They might be useful for simple procedures like central line insertion, but they are hardly a panacea for the myriad ills of modern medicine. Patients are too varied, their physiologies too diverse and our knowledge still too limited."<p>The problem is that everyone (including doctors) overestimates both their ability to diagnose based on instinct, and the percentage of patients who deviate from the norm.<p>For heart attacks, they found that a 3 step checklist was X% effective in diagnosing a heart attack, while the doctor alone was Y%, and X was much higher than Y.  Yes, sometimes the doctor would use his expertise to catch something the checklist would miss, but over time the math was with the checklist.