don't need doctors anymore

(Posted on Angry Doctor.)

Concerned patient commented in an earlier post:

I find that doctors do too many tests these days. Can't they just be sure about something without having to do tests? It costs $8+ to consult a doctor at the polyclinic but $10+ for a test. Is the test worth more than the doctor? From where the money goes it seems to be the case.

maybe we don't need doctors anymore.

There are actually a few interesting observations to be made here.First of all, it tells us that when a service is priced too lowly, it is also valued lowly; something that perhaps the Ministry of Health would do well to consider.

The question of whether doctors do too many tests is also an interesting one. To be more specific, we need to ask: are doctors ordering than they need to be sure of what?

To be sure that they can make the diagnosis?

Or to be sure that they will be able to cover themselves in a court of law?

The reality on the ground is probably a mix of both. To conduct an accurate study of the situation one would theoretically need every case to be audited by one or more doctors - clearly an unrealistic proposition.

But what angry doc is really interested in discussing is the idea conveyed in the last sentence: that tests render doctors obsolete.

Once again, we witness the arrogance of ignorance.

Tests do have their place in the management of patients. They allow doctors access to facts they wouldn't otherwise be able to have using only their senses, and help them come to the diagnosis. But too often patients think that there is a test for every symptom or set of symptoms that would effectively diagnose a condition, and that the process of diagnosis involves simply ordering every test from a 'menu', and the results will give us the diagnosis, which then allows us to institute the treatment. Wrong.

There are literally hundreds of tests you can order from a standard laboratory and imaging ordering form - the doctor's job is to decide which few out of these to order based on the patient's presentation and therefore possible and likely diagnoses. Granted there are 'panels' and 'batteries' of tests which are often 'packaged' together for operational ease, but angry doc bets most doctors would rather do away with these and to tick more boxes on the form than to have to deal with all the incidental mildly-elevated AST that crops up far too often; what tests a doctor orders is sometimes as important as what tests he does not order - we want 'actionable intelligence', not 'noise'.

Similarly, a doctor will be ordering tests to get the positive results he expects, as well as the negative results he expects, because ruling out a diagnosis (or several diagnoses) is also an important part of arriving at a diagnosis.

Once all that thinking had been done and the results are available, the doctor still has to interpret the results and see how they apply to the patient. This involves an understanding of the false positive and false negative rates, as well as pre-test probabilities, all of which will tell us if a positive test really means our patient really has a disease, or if a negative test really means he really does not, and which is very clearly illustrated in this wikipedia entry.

Will they come up with a computer programme someday that can elicit a history and perform the required physical examination to arrive at a list of differential diagnoses, and which can determine which tests to order to eliminate and ultimately confirm diagnoses from that list, and subsequently come up with the recommended management?

Probably.

But they haven't. And until then angry doc thinks he deserves more than $8+ to do all that thinking. Don't you?