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. 2006 May;1(1):e9.
doi: 10.1371/journal.pctr.0010009.

Factors that can affect the external validity of randomised controlled trials

Peter M Rothwell  1
Affiliations

Factors that can affect the external validity of randomised controlled trials

Peter M Rothwell. PLoS Clin Trials. 2006 May.
No abstract available

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Conflict of interest statement

Competing Interests: The author declares that he has no competing interests.

Figures

Figure 1
Figure 1. The Absolute Reductions in the Five-Year Risks of Ipsilateral Ischaemic Stroke (Top) and Any Stroke or Death (Bottom) with Surgery in European Carotid Surgery Trial Centres in Which the Median Delay from Last Symptomatic Event to Randomisation Was Less than or Equal to 50 Days (Fast Centres) Compared with Centres with a Longer Delay (Slow Centres)
Data are shown separately for patients with moderate (50%–69%) and severe (70%–99%) carotid stenosis.
See this image and copyright information in PMC

References

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