Diagnostic accuracy: sailing for remote islands?

Physicians` diagnostic accuracy has been estimated around 55% for easy cases and 6% for difficult cases before a definitive diagnosis is reached (1).  But with this wide margin for improvement, why are doctors so reluctant to ask for help?..

(1)Gurpreet Dhaliwal, MD. JAMA Internal Medicine November 25, 2013 Volume 173, Number 21

Greater case difficulty was correlated with increased requests for reference materials but  input from colleagues was not common. One of the reasons for this overconfidence is in my opinion that doctors have switched the clinical reasoning process for the expectation of the diagnostic test. In an study over 25 patients attended in an Internal Medicine Department and presented for our group in the last SDIM 2013, around 64% of patient had a final diagnosis obtained after a biopsy. Maybe the confidence in the result of a test or biopsy is targeting the elaboration of a proper differential diagnosis.