How do they determine statistics like “8 million people in the US have __ disease and another 1 million are undiagnosed”?

Question

I work in healthcare and there have been multiple times where I’ve seen disease prevalance statistics that include “undiagnosed cases”. If they have not been diagnosed then where do they get those numbers from?

In: 29

Answer 1

Hi!

The statistical methods are really quite easy.

For some things, like diabetes they can look at hospital records.

Lets say they look at records for 1/1000th of the population (that would be medical records for 33k people). They can look at 10 different hospitals (3.3k records each) and see the actual number of people who have diabetes of those 33k people) From here they estimate the number (multiply by 1000) in the whole population.

There are things they do with the data to make it more accurate and account for data oddities, but those are more complex.

To estimate the number or percent undiagnosed they make some assumptions like what age were people actually diagnosed, and are people under a certain age likely to have the condition but not be diagnosed yet.