Absolute Risk vs Relative Risk

We’ve all seen this, a drug claiming incredible results. Anyone reading this would think, “Wow, they just reduced the risk by half.  So, a 2% chance of a heart attack is now only 1%. If you thought this was correct, you are wrong. Let’s assume in this example a 5-year risk for heart attack is 2 in 100 (2%).  A group of patients treated with the new drug report a 1 in 100 or a 1% occurrence of heart attacks; the absolute difference is 1%.

By simply subtracting the two risks: 2% – 1%, you get 1%, but when we see claims depicted in the illustration above, they are not using absolute risks; they’re using relative risk, which is entirely different.  They take 1 is 50% of 2, so a 50% of 2, so a 50% reduction is pretty sketchy fudgery of the odds if you ask me. So why is this important for me to understand? It’s vital if you want to know the truth and have all the honest facts.

Stick with me; I will explain this as best I can. Using the above example that used relative risks, look how it reads if we rewrite this to use absolute risk. The absolute risk looks small and less Impressive. In other words, the pharmaceutical industry wants the benefits to look more prominent and the harms to look smaller. This is called mismatched framing and usually never gets picked up by us who make decisions based on this data reporting wizardry. This needs to be understood, and you need to know when it’s being used. Although absolute risk and relative risk are both accurate, one may be terribly misleading. If someone is trying to sell you on something, they are likely to only use relative risks when talking about benefits and absolute risks when talking about risks. 

The COVID19 – Mismatched Framing Reality:

When COVID first came about, scientists started releasing information and soon the media caught onto the story, and soon a hornet’s nest of mismatched framing was unleashed. I recall trying to explain what was going on back in March of 2020, but people seem to be too caught up in the panic for any reception of logical thought. What was reported was as follows: It was reported in early estimates a 4% chance of catching COVID and then a 2% chance of ending up in an ICU, then finally, a further 2% risk of dying. People interpreted this to mean a 2% chance of dying from COVID, and the panic ensued. We know now, or at least I hope we do, and if you have been keeping up-to-date with my posts, you would know,  the risks of dying from COVID is more in the order of .00024%, which is a huge disparity in odds compared to the 2% once thought to be the number.  An absolute 4% chance of catching covid, then a “relative” 2% chance for those people ending up in a hospital, and of those people, a further “relative” 2% chance dying. A percent of a percent, of a percent.

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