December 24, 2021

AMA #30: How To Read And Understand Scientific Studies| The Drive with Peter Attia #188

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Key Takeaways

• It’s a valuable skill to be able to sift through the noise and find the signal in scientific studies
• Though meta-analyses summarize findings from previous studies, it’s still prudent to look at each individual study to make sure they’re sound – garbage in, garbage out (and vice versa)
• Observational studies are non-intervention studies looking at the outcomes of people and data to find patterns
• Experimental studies are intervention studies to determine safety and efficacy between groups of people assigned to intervention or control (non-intervention)
• The gold standard of experimental studies is a randomized controlled trial, ideally, double-blind so neither participant nor researcher knows who is assigned to intervention or control
• While clinical trials are regulated by FDA, most of the world follows the same guidelines for Phases I – IV

Introduction

In this special episode of The Drive, Peter Attia sits down with Head of Research at Attia Medical, PC Bob Kaplan (@bobkaplan) to take a deep dive into reading & understanding studies. Attia highlights how to find the important points, defines various types of studies, the evolution of studies from idea to execution, and much more. Note, this is only a preview. The full episode is only available to subscribers.

Host: Peter Attia (@PeterAttiaMD)

How Does A Study Go From Idea To Execution

• Good science is hypothesis-driven
• Studies are often guided by the null hypothesis versus the alternative hypothesis
  • Null hypothesis: there is no relationship between two phenomena
  • Alternative hypothesis: there is a relationship between the phenomena
• The gold standard to test the hypothesis is an experimental design, randomized controlled trial – ideally, be double-blinded

Different Types Of Studies

• Study design can be broken down into a few categories: (1) observational studies; (2) experimental studies; (3) meta-analysis or review
• Observational studies – no intervention, just looking at data and people to find patterns
  • Individual case report: dive into one specific patient case that is driven by an observation that has not been studied before and can inform future treatment
  • Case studies: similar to individual case reports but with a larger set of patients
  • Retrospective cohort study: observational (not intervention) look back at a set of people who took part in ‘x’ and see how they are doing today versus people who did not take part in ‘x’
  • The goal of cohort studies is to establish a pattern and potentially determine casualty
  • Prospective cohort study: follow people who use ‘x’ over the next 5-10 years and compare them to people who do not use ‘x’ and observe outcomes
• Experimental studies – intervention
  • Non-randomized trial (AKA open-label trial): two groups of people either given placebo or intervention but not randomized; grouping people based on certain characteristics
    • Comes with a lot of bias because there is a reason you put certain people in a group
    • Patients can also self-select into this type of study
  • Randomized controlled trial: the gold standard of experimental design; study the question but take bias out by randomly assigning people to treatment or control group
• Meta-analyses: combine data from multiple studies that are attempting to look at the same question
  • This seems great on the surface but is highly dependent on the quality of the original studies: garbage in, garbage out – and vice versa
  • You can gain great insight from meta-analyses but take a closer look and examine each of the studies within the analyses

Phases Of Clinical Trials

• FDA clinical trials: drug or therapeutic you think will have some benefit in humans after showing success in animal models
• The first step is to file an investigational new drug (IND) application showing pre-clinical work and setting an intention to study in humans
• Phase I: small studies to determine toxicity (not whether the drug works) in a range of doses with efficacy
• Phase I studies look to see whether drug hurts, not how well it works
• Phase II: evaluate the safety and start exploring efficacy through open-label, usually non-randomized design
• Phase II studies are small and will compare to the natural history of patient outcomes to start examining the efficacy
• The goal is to randomize Phase II but patients will often self-select or doctors will recommend
• If drug or therapeutic has been deemed safe enough for use and has some efficacy, it will move on to Phase III
• Phase III: huge step up from Phase II studies; this is a randomized controlled trial and ideally blinded with the goal of measuring efficacy and determining broad use
• Phase IV: post-marketing study after the drug has been approved and uses information from a broader audience and exploring potential off-label uses or additional side effects

To learn more: subscribe and/or read Peter Attia’s series, Studying Studies.

Drive with Dr. Peter Attia : health, randomized controlled trials, scientific writing, studies
Notes By Maryann