Ioannidis, "Why Most Published Research Findings Are False" (PLoS Medicine)

John Ioannidis · 30 Aug 2005 · journals.plos.org ↗

6 korrents from this paper

In plain words

Most published research findings are false because studies are often too small, effects too weak, methods too flexible, and too many teams race for positive results. It shows why so many claims fail later and why findings can simply track a field’s bias instead of real effects. An opinion essay models the odds a claim is true and argues against treating one significant study as proof.

Our summary of the paper, not the authors' words — written to be readable without the field's vocabulary, from the stored copy of the paper and nothing else. Drafted with xai:grok-4.5 and checked by a person. The authors' own sentences are the quotes below.

John Ioannidis did not write this page.

Every claim below was made in this piece, quoted word for word and numbered in the order the piece makes them, so you can read it there rather than take our word for it. The sentence above each quote is our reading of the claim, not their wording. Each quote was checked against a stored copy of the page at build time; where the two differ, the quote is the fact.

Our reading
Most claimed research findings are false, and that can be shown rather than merely suspected.

Their wordsIt can be proven that most claimed research findings are false. Here I will examine the key factors that influence this problem

Interesting
Our reading
The smaller the studies a field runs, the less likely its published findings are to be true.

Their wordsThe smaller the studies conducted in a scientific field, the less likely the research findings are to be true.

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Our reading
The smaller the effects a field studies, the less likely its published findings are to be true.

Their wordsThe smaller the effect sizes in a scientific field, the less likely the research findings are to be true.

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Our reading
The more analytical freedom a field allows in designs, definitions and outcomes, the less likely its published findings are to be true.

Their wordsThe greater the flexibility in designs, definitions, outcomes, and analytical modes in a scientific field, the less likely the research findings are to be true.

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Our reading
The greater the financial interests and prejudices in a field, the less likely its published findings are to be true.

Their wordsThe greater the financial and other interests and prejudices in a scientific field, the less likely the research findings are to be true.

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Our reading
A hotter field with more teams racing on the same question produces less reliable findings, not more.

Their wordsThe hotter a scientific field (with more scientific teams involved), the less likely the research findings are to be true.

Interesting