Frequent readers may remember that I love mysteries. I believe that accounts for my love of morning report and CPCs. Many general internists share this love for a genre which closely parallels our field.

For those with access – White coats and fingerprints: diagnostic reasoning in medicine and investigative methods of fictional detectives

Current trends toward routine mass use of sophisticated diagnostic tools is killing off the science and art of clinical reasoning. An ideal clinician would present a harmonic fusion of almost all the investigative methods of fictional detectives and avoid slavish adherence to protocols and procedures

Our underlying premise is that the current trend towards mass use of sophisticated diagnostic tools in routine practice—accompanied by a blind faith in technology and predefined diagnostic algorithms—is threatening to kill off the science and art of clinical reasoning. Besides burning a lot of public and private money to make diagnostic work rather superficial, doctors also risk losing the intellectual pleasure that comes from careful diagnostic reasoning.

Clinical analogies with detective fiction generally revolve around Sherlock Holmes.1 2 However, like medicine, detective fiction has subspecialties and intellectual trends.3 A rapid overview of the analogies between diagnostic reasoning and the investigative strategies found in detective literature may provide us with some clues on how to confront the problems posed by the burgeoning number of available technologies.

I disagree with the initial assessment because the authors leave out an important factor. No diagnostic test helps if we do not know to order the test. The intellectual challenge of internal medicine in 2005 remains active. Patients come in with vague complaints, which we must sort through using history and physical clues. These clues help us develop a differential diagnosis (a list of possibilities) which we can rank as to likelihood. Then, and only then, should we use technology to sort through the possibilities.

We could take everyone who comes in with vague complaints and order a “man scan” (the resident’s slang for total body CT scanning). But this strategy would yield too many red herrings, and still not find the underlying problem very often.

After the somewhat depressing introduction, the authors redeem themselves by discussing in beautiful terms the type of reasoning that various famous detectives use. Their final paragraph is classic!

An ideal clinician could be said to present a harmonic fusion of almost all the investigative models outlined above—a rare event. If one investigative quality marks out the mature clinician it is the ability to spot possible inconsistencies among the clinical, instrumental, and laboratory examinations, considering not only what is present but also what is missing. This requires skills in observation and “deduction,” handling of knowledge, pattern recognition, and the astuteness that comes from years of experience. For well honed clinicians, the clinical part of the diagnostic investigation is not just a question of medical history and physical examination but rather the capacity to establish links among various physical and laboratory or instrumental findings with an eye to both the consistencies and inconsistencies. In this context, simple examinations really do have the same value as the more complex and expensive ones.

Bravo! Bravo!! (here db stands for an ovation)