👇 See how changing the included studies changes this result.
I explain it more fully in my blog post, but this page is an experiment to see how we can improve medical information on the internet.
I believe that good medical communication is quantitative, exhaustive, and accessible—this page strives as much as possible to be all three!
Welcome to the forest plot! Each row represents a (randomized, controlled) clinical trial, and the 𝚫 column tells you the percent change in cold duration between the zinc group and the placebo group for that trial (negative numbers mean the zinc group had shorter colds).
The middle columns show which trials were included in the existing systematic reviews on zinc lozenges. Try clicking on the headers to see their results!
Last updated ???
Every week I search the Cochrane Central Register of Controlled Trials (CENTRAL), which aggregates results from other popular databases like PubMed, Embase, and ClinicalTrials.gov.
I then exclude the results that aren't relevant (see adjacent panel). My screening criteria are intentionally lax—the point of this page is to provide an exhaustive list of relevant data, and let visitors decide which trials are worth looking at.
zinc AND cold
Funnel plots are used to gauge whether the results of candidate reviews are distributed like we'd expect.
For a given set of trials, we'd expect large trials to have outcomes that cluster close to the true effect size (the top of the funnel), while smaller trials would have outcomes that are more widely distributed (the bottom of the funnel).
In theory, 95% of trial results should lie inside the funnel. In addition, these results should be distributed symmetrically on either side of the pooled effect size (center line).