Can you have too many tests?

(Hint: Yes.)

Screening and diagnostic tests are valuable tools in helping doctors to prevent illnesses, find medical conditions at early treatable stages, and identify or exclude medical conditions as causes of patient symptoms.  By definition, screening tests (such as annual cholesterol testing: can we keep you from having a heart attack) are done to prevent problems or to identify them before they have actually started to cause problems.  Diagnostic tests (such as heart muscle enzyme tests: are you having a heart attack) are done due to symptoms or other problems.

Doctors learn as early as medical school that just the right amount of testing is the best.  Too little can lead to delays in diagnosis and treatment, too many can confuse the matter by raising "red herrings".

Theranos is one of the most heavily financed start-ups in history.  The company proposes break-through technology which would allow most blood tests to be performed on no more blood than a relatively painless prick of the finger (rather similar to what diabetics do to check their blood sugar).  Their eventual goal seems to be to set up free-standing labs in retail locations such as Walgreen's that would allow people to pay for any lab test as often as they want without requiring a doctor's order.  Presently, the company is beset by serious questions regarding data they seem to have generated using standard lab testing equipment and a number of other major issues. (The Wall Street Journal has quite a bit of coverage on this, but it is pay-walled.)

I don't have any financial stake in any labs or X-Ray facilities and am generally in favor of transparency and the exercise of free will.  Frankly, I imagine I would be seeing patients who are concerned about abnormal tests as often as I already see patients for abnormal symptoms if Theranos were already up and running.  In other words, I would not find their existence threatening.

My issue with Theranos' proposal is that selecting and interpreting tests is complex.  (As in if it wasn't so complex, pathology wouldn't me a medical specialty and medicine wouldn't be a profession.) 

• If you are concerned about a specific condition, you have to know what tests will help to identify and/or exclude it.
• You have to know when a test result that is outside the reference range is significant and when it is benign.
• You have to know when results that are technically within the reference range are significant.
• You have to be prepared to act on expected and on unexpected results.

Katherine Hobson at FiveThirtyEight does a great job at addressing the greater concern; we don't necessarily need more tests.

Side windows let more UV in than we thought

We have known for some time now that Americans get more skin cancers on the left side of sun-exposed areas like the forearm, face and neck since we drive on the side of the car (and we do drive a lot).

More recently, it seems that the amount of ultraviolet (UV) sunlight that can get through the closed side window of cars can be quite high. 

The windshield typically blocks 96% of UV.  This is due to its 2-layer construction that makes it hard to shatter in a crash.  On the other hand, side windows are not required to be so crash-safe.  Some models (such as Lexus) block as much as the windshield.  Others only block about 70%.

Until side windows catch up, the best way to prevent skin cancers due to this exposure is to apply some sunscreen before you drive.

It's also worth remembering that applying some SPF 30 every day (even if you are not going out) prevents skin cancer, both prevents and reduces freckling and moles, and also prevents sun-related wrinkling and aging of the skin!

Medical Errors

A recent article in British Medical Journal looked at the occurrence of fatal medical errors in a group of US hospitals and found that if the error rates found in this group of North Carolina hospitals applied nationwide, it would make fatal medical errors the third most common cause of death in the US (falling between cancer and COPD).

On the one hand, this article did not break down the findings as to what causes of medical errors were found.  It also assumes that the errors found in this group of hospitals does apply to all hospitals in the US.

On the other hand, if it even comes close to being an accurate projection that ain't good! 

The possible causes of fatal medical errors are numerous.  The potential for communication errors is high, given the number or parties and third parties involved: patient, doctor, family, office staff, pharmacy, insurance company, "mail-order pharmacy", etc., etc.

The introduction and requirement for electronic medical/health records (EMR/EHR) is probably not helping.  Doctors, nurses and pharmacists all have different parts of it and they sometimes don't overlap.  Remember the first US Ebola patient who showed up in an ER in Texas?  The patient was asked about recent foreign travel, he truthfully answered yes, the nurse responsibly checked the box "Yes" on the question of recent foreign travel but it did not appear in the doctor's information at all.  This break up of information flow is intended to keep people with different tasks from being overwhelmed with information not directly relevant to their tasks and is a common feature of most EHR's.

The design of EHR is quite poor.  Some studies show doctors spending 44% of their time on data entry and 28% of their time on actually care of the patients.  Frankly, it makes me glad I never fully bought into EHR!

I hope this article prompts us all to take a real hard look at our present methods or error reduction and find ways to quickly and effectively improve on them.