#188 - AMA #30: How to Read and Understand Scientific Studies

In this "Ask Me Anything" (AMA) episode, Peter and Bob dive deep into all things related to studying studies to help one sift through all the noise to find the signal. They define the various types of studies, how a study progresses from idea to execution, and how to identify study strengths and limitations. They explain how clinical trials work, as well as the potential for bias and common pitfalls to watch out for. They dig into key factors that contribute to the rigor (or lack thereof) of an experiment, and they discuss how to measure effect size, differentiate relative risk from absolute risk, and what it really means when a study is statistically significant. Finally, Peter lays out his personal process when reading through scientific papers.

If you're not a subscriber and listening on a podcast player, you'll only be able to hear a preview of the AMA. If you're a subscriber, you can now listen to this full episode on your private RSS feed or on our website at the AMA #30 show notes page. If you are not a subscriber, you can learn more about the subscriber benefits here.

We discuss:

• The ever changing landscape of scientific literature [2:15];
  
• The process for a study to progress from idea to design to execution [4:15];
  
• The various types of studies and how they differ [7:30];
  
• The different phases of a clinical trial [19:15];
  
• Observational studies and the potential for bias [26:30];
  
• Experimental studies: Randomization, blinding, and other factors that make or break a study [44:00];
  
• Power, p-values, and statistical significance [56:15];
  
• Measuring effect size: Relative risk vs. absolute risk, hazard ratios, and "Number Needed to Treat" [1:07:45];
  
• How to interpret confidence intervals [1:17:30];
  
• Why a study might be stopped before its completion [1:23:45];
  
• Why only a fraction of studies are ever published and how to combat publication bias [1:31:30];
  
• Why certain journals are more respected than others [1:40:30];
  
• Peter's process when reading a scientific paper [1:43:45]; and
  
• More.