Reading Between the Drops Part 2- Understanding Dry Eye Research

Becoming better consumers of medical research is something all patients can try to do. Last time we suggested asking these two questions when you read a study.

1. Does the hypothesis make sense?

2. Does the experiment make sense?

Here’s another question you can ask yourself. It might help you read between the drops and become an even better consumer of medical research.

3. Does the conclusion make sense?

Let’s say you’re reading a study about a new treatment. Pretty soon you skip to the conclusion because there are so many medical and statistical terms that your head is spinning. And because you have Dry Eye, your eyes hurt too.

Reading Between the Drops Part 2
Reading Between the Drops Part 2

So what do you find in the conclusion? The researchers probably say the product they studied is an effective treatment for the disease.

Should you be concerned or surprised?

No. Not if patients who participated in the study really improved.

But how do you know the researchers aren’t making outsized claims? How can you tell they’re not overstating the facts? How can you tell if patients really improved?

One way to verify what the researchers conclude is to check their numbers. You’ll find the numbers in the Results section of the summary.

Yes, most of the time the numbers will be extremely confusing. You’ll be tempted to skip over them. It’s statistics after all. And since most of us haven’t studied statistics we’re not going to get into a long lesson in statistical analysis.

But we will say this. The numbers have to add up.

Here’s what we mean.

1 + 1 = 2, Always

If the results indicate that 90% of patients improved, great. 90% is practically 100%, and that’s a lot of people who feel better.

But what if the math looks like this.

Of 100% of people studied:

15% of people improved with treatment
5% of people improved without treatment

What about the other 80 – 85%, because

100% – 15% = 85% – 5% = 80%

Here’s a real-world example of a study with math exactly like that.

…in approximately 1,200 patients with moderate to severe …Dry Eye…This effect was seen in approximately 15% of treated patients versus approximately 5% of vehicle-treated patients.

(Vehicle just means a drop without the product being tested added).

So it’s the exact same math. Math is math. 1 + 1 = 2.  That never changes.

You get the exact same equation:

100% – 15% = 85% – 5% = 80%

What About the Other 80%?

But now, ask yourself, what about the other 80% that didn’t improve? What about them? After all, 80% is a lot of patients who don’t feel better, especially if the researchers conclude that xyz is an effective treatment. 

And what if the 80% are prescribed a treatment that only helps the 15%?

That’s a lot of unnecessary prescriptions, a lot of wasted money (if you’re a patient – not if you’re the drug company), and something serious to think about.

Find out which Dry Eye treatment was the subject of this study.

So if you see a study, and it’s about a product your doctor recommends, don’t be afraid to ask, “Am I going to be in the % that improves, or in the % that doesn’t benefit from the treatment at all?”

Then together, you and your doctor can decide if this treatment makes sense for you to try. Are you a candidate or not? Will it help you, or not? And if yes, how much?

Next time we’ll look into financial disclosures, where studies are published, and what it all means. And we promise, there won’t be any math…maybe.

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