Chart assignment

Charts to read and discuss

Read each chart, then answer its questions. Every chart shows its source and date; open it for a table of the numbers and the data to download.

  1. How many finished clinical trials post their results?

Chart 1 of 1 · Clinical trials

How many finished clinical trials post their results?

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21.5% of the clinical trials completed in 2024 had posted results on ClinicalTrials.gov by November 2026, down from 35.6% of those completed in 2008, when a U.S. law began requiring results for many trials. That law covers mainly U.S. trials of drugs and devices past Phase 1, so many trials, including most outside the U.S., don't have to post here; some publish results in journals instead. Results are due a year after a trial ends, so the chart stops two years back, and a year's share can still rise.

Questions to discuss

  1. In one sentence of your own, what does this chart show?
  2. Find the biggest change or difference in the chart. What might explain it?
  3. Who collected these numbers, and how recent are they? What else would you want to know before drawing a conclusion?

Source: ClinicalTrials.gov (U.S. National Library of Medicine), counted with its API v2 (Public domain (U.S. government work); source National Library of Medicine) · Data as of Nov 4, 2026

Open the chart and its numbers

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