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Avoiding misleading reporting on systematic reviews & meta-analyses

Avoiding misleading reporting on systematic reviews & meta-analyses

Slides from a short presentation at the World Conference of Science Journalists in 2019, with links to backgrounder posts.

Hilda Bastian

July 02, 2019
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  1. Avoiding Misleading
    Reporting on
    Systematic Reviews &
    Meta-analyses
    World Conference of Science Journalists
    Lausanne
    2 July 2019
    Hilda Bastian
    @hildabast
    hildabastian.net

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  2. Studies are a collection of parts of
    uneven quality & quantity [+ spin]

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  3. Pitfall 1: Exaggerating the quantity of
    evidence
    https://well.blogs.nytimes.com/2016/06/27/putting-breast-cancer-on-a-diet/
    1

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  4. •  82 studies, published 31 meta-analyses
    •  84% of those analyses combined 20 or fewer
    studies – 58% had 10 or fewer
    •  The most studies in any one meta-analysis
    was 24
    https://academic.oup.com/annonc/article/25/10/1901/2801213

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  5. Common error: exaggerating the amount
    of evidence
    https://well.blogs.nytimes.com/2016/06/27/putting-breast-cancer-on-a-diet/

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  6. 21 studies with approx 42,000 women

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  7. 2
    . . .

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  8. Sherrington et al (2019). Exercise for preventing falls in older people living in the community.
    https://www.cochranelibrary.com/cdsr/doi/10.1002/14651858.CD012424.pub2/full
    8 studies with fewer than 2,700 people

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  9. From the Summary of Findings table:

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  10. Pitfall 2: Overestimating the strength of
    evidence

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  12. 3

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  13. From 2008 Cochrane review:
    https://doi.org/10.1002/14651858.CD001321.pub4

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  14. From 2008:
    Update in 2012:

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  15. 5 tips for understanding data in meta-analysis: bit.ly/5TipsData
    5 key things to know about meta-analysis: bit.ly/MetaBasics
    Another 5 things to know about meta-analysis: bit.ly/MetaTraps
    Systematic reviews & meta-analyses 5 step checkup: bit.ly/MetaCheckup

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