Evidence-Based Medicine

[EBM] Should I calculate study power when results are not significant? Misleading post-hoc power

When reading papers or doing research and hitting a non-significant result, I always remember what my statistics teacher said: “Not significant means we cannot reject the null hypothesis, not that the two are the same.” We’ve also learned that the ability to detect a difference between the two is called statistical power. So, if we calculate the power of the data, and if this “ability to detect a difference” is greater than 80%, but we still get a non-significant result, does that mean the two groups of data are really similar? ...

<Systematic Review Workshop> Takeaway 1: Do we use PICO for diagnostic, prognostic, and harmfulness studies?

Prof. Edwin Chan is the Director of Cochrane Singapore. He’s considered a master of EBM and systematic reviews in Asia, with extensive academic experience. We were honored and lucky to have Hualien Tzu Chi Hospital invite him to hold a one-day workshop for us on December 5, 2018. To see a master like him, I rushed back to Hualien from Dalin, Chiayi, even if it meant taking the night train (it’s a long journey!). Over the next few posts, I’ll share a few key takeaways that left a deep impression on me. ...

Systematic Review Workshop Takeaway 2: Are Few Search Results a Sign of a Good Search Strategy?

After talking about setting a precise question (PICO), let’s look at the search results! We know that sometimes we see a situation where the results give us two thousand papers. That’s definitely overwhelming, making you doubt whether your keywords weren’t good enough, and so on. But, did you think you could just clap your hands in satisfaction when there are only 5 results!? (Well, obviously yes when you’re rushing to finish a report xD) ...