09 BiggestSecretinMedicine

TL;DR

Understanding the difference between relative risk and absolute risk difference is key in evaluating the effectiveness of medications.

Transcript

if you've been with me this far you deserve a little something so i'm going to let you in on a big secret we have in medicine what i call the biggest secret in medicine um to get there though i'm going to need to describe to you the difference between the relative risk and the absolute risk difference and introduce the concept called number needed ... Read More

Key Insights

• 😷 Medical studies evaluate the effects of medications on a population, not individual outcomes.
• ✳️ Relative risk and absolute risk difference are different metrics used to express medication effectiveness.
• ✳️ Relative risk can inflate the perceived effectiveness, while absolute risk difference provides a more accurate picture.
• 🪡 The number needed to treat helps assess the likelihood of an individual benefiting from a medication.

Questions & Answers

Q: What is the difference between relative risk and absolute risk difference?

Relative risk compares the risks of an outcome between two groups, often expressed as a percentage, while absolute risk difference measures the actual difference in risk between the two groups.

Q: How can relative risk be misleading?

Relative risk can be misleading because it often sounds more impressive than absolute risk difference, giving a larger perception of the effectiveness of a medication.

Q: What is the number needed to treat (NNT)?

The NNT represents the number of people who need to be treated with a medication to prevent one additional bad outcome, such as a heart attack. It is calculated as the inverse of the absolute risk difference.

Q: Is the NNT a universal threshold for the effectiveness of medications?

No, the NNT does not have a specific threshold. It depends on the individual's risk profile, the cost and side effects of the medication, and the perceived benefit of preventing the bad outcome.

Summary & Key Takeaways

• Medical studies assess the effects of medications on a population, not individual outcomes, similar to the odds of winning in a casino.

• Relative risk and absolute risk difference are two metrics commonly used in medical studies to express the effectiveness of a medication.

• The number needed to treat (NNT) is the inverse of the absolute risk difference and helps determine the likelihood of a medication benefiting an individual.