Anyone who has ever had a major medical issue—even a routine surgery—is familiar with the process of blood work. Laboratory tests, evaluating the blood for potential abnormalities, are a staple of modern healthcare, so much so that blood tests are generally included in annual physicals and routine diagnostics. Hopefully, you’ve enjoyed such sterling health that there’s never been anything the least bit worrisome or out of the ordinary about your own blood work.
But one day, that day may come. The physician may enter the waiting room to explain the results of your blood work, and the report may be something considerably less than glowing. The doctor may tell you that there are some concerns in your blood work—some results that are outside the range of “normal.” And then what?
Putting Blood Work into Perspective
Blood tests can certainly be useful in providing physicians with some basic health metrics and parameters—but let us be clear from the outset: Even if you have abnormal blood results, it does not necessarily mean you need to be worried.
Why is that? Because blood tests don’t work the way many assume they do. They are not straightforward assessments of health; they’re not report cards, assigning you a basic A-F score. Rather, they are used to determine whether a particular disease or something irregular is present in your body. Normal blood work means that no sign of the disease is spotted—but even abnormal blood work is not necessarily proof that there’s something wrong.
Range of References
Instead of thinking about your lab results in terms of a report card, consider them like a reference range.
Generally, lab results provide an indicator of what healthy blood looks like for 95 percent of the population. The implication here is that about 5 percent of the healthy population lands somewhere beyond this “normal” range. To put it differently, a not-insignificant portion of healthy people have blood work that may appear worrisome, problematic, or simply not normal. Yet, their blood work does not mean that they have an illness or that there is anything wrong with them.
That range was determined simply by testing a lot of blood from a lot of people, and averaging what seems normal. The major Blood Labs in the US change their ranges from time to time and the group of people that make up the data may not be exactly similar to you, in spite of the claims. Also as science evolves the accuracy and efficacy of these tests evolve too. Now, falling outside this range of normalcy can certainly point physicians toward further testing or observation, but these results need to be taken in the proper context: What’s “normal” for one person simply may not be “normal” for someone else; what’s good and healthy for you may be outside the traditional range, and that’s okay. Additionally, technology regarding blood tests and others is about to rapidly explode. We will soon see better more accurate, easier testing methods become commonplace.
The Reliability of Blood Work
There are a couple of other concepts that you need to consider as you think about your blood work. First, there is the concept of variability. Basically, you can have the exact same blood test done three different times and get three different results. So if you have a slightly abnormal result from one test, the best approach may be to just check it again later. (Hopefully, your tests will all be somewhat close to one another, even if they are not identical.)
And that’s the concept called reliability: Basically, a test can sometimes be performed multiple times just to ensure accuracy.
Keep these things in mind as you think about the results to your blood work—but more importantly, seek medical counsel to help you in the interpretation. Get your doctor to walk you through the implications of your blood work, and what the next steps might be. Don’t ever assume that an “abnormal” lab test is anything to be frightened about.